hadron2011

Jun 12, 2011, 8:00 AM → Jun 17, 2011, 6:00 PM Europe/Berlin

Künstlerhaus

Nora Brambilla (Physik Department, TU Munich), Stephan Paul (TU-München)

XIV International Conference on Hadron Spectroscopy

Sunday, June 12

4:00 PM Registration and wine social

Monday, June 13

Plenary Session: 1

Convener: Dr Suh-Urk CHUNG (E18/TU)

1 Opening Remarks

Speaker: Prof. Stephan Paul (TU-München)

2 Low-Energy Pion-Photon Reactions and Chiral Symmetry

In this talk, I review the description of low-energy pion-Compton scattering in chiral perturbation theory. At one-loop order, the effects due to the pion structure consist of the electric and magnetic polarizabilities (subject to the constraint $\alpha_\pi+\beta_\pi =0$) and a unique pion-loop correction interpretable as photon scattering off the ``pion-cloud around the pion''. The latter compensates in the differential cross section $d\sigma/d\Omega_{cm}$ partly the reduction effects due to the polarizabilities \cite{picross}. The two-loop corrections to charged pion-Compton scattering, first calculated by Bürgi [1] and recently completed and reevaluated by Gasser et al. [2] are relatively small in the low-energy region $\sqrt{s}<4m_\pi$. Therefore chiral perturbation theory leads to firm predictions for the pion polarizabilities [2]: $\alpha_\pi-\beta_\pi = (5.7\pm 1.0) \cdot 10^{-4} fm^3$ and $\alpha_\pi+ \beta_\pi = 0.16\cdot 10^{-4} fm^3$. Because of the smallness of the pion-structure effects (less than 20 %) radiative corrections of order $\alpha$ have to be included also in the analysis of pion-Compton scattering data. It is found that these QED radiative corrections \cite{radcor} have the same kinematical signature as the polarizability difference $\alpha_\pi-\beta_\pi$, but their effects are suppressed in magnitude by about a factor 5 or more. The other topic of my talk is the description of the (charged and neutral) pion-pair photoproduction processes $\pi^-\gamma \to \pi^- \pi^0\pi^0$ and $\pi^-\gamma \to \pi^+ \pi^-\pi^-$ at next-to-leading order in chiral perturbation theory [3]. Whereas the total cross section $\sigma_{tot}(s)$ for the neutral channel $\pi^-\gamma \to \pi^- \pi^0\pi^0$ gets enhanced sizeably by the inclusion of chiral loop and counterterm corrections, the analogous effects turn out to be very small for the charged channel $\pi^-\gamma \to \pi^+ \pi^-\pi^-$. This different behavior can be understood from the varying influence of the chiral corrections on the pion-pion final state interaction ($\pi^+\pi^-\to \pi^0\pi^0$ versus $\pi^-\pi^- \to \pi^-\pi^-$). The QED radiative corrections have also been calculated for the process $\pi^-\gamma \to \pi^- \pi^0\pi^0$ (simpler case) [3]. These affect the total cross section by at most 2 %. The predictions of chiral perturbation theory for low-energy pion-photon reactions can be tested soon by the COMPASS experiment at CERN which uses Primakoff scattering of high-energy pions in the Coulomb-field of a heavy nucleus. A preliminary analysis for $\pi^-\gamma \to \pi^+ \pi^-\pi^-$ in the energy region $3m_\pi < \sqrt{s} < 5m_\pi$ confirms the prediction of chiral perturbation theory. [1] U. Bürgi, Nucl. Phys. B479 (1996) 392; Phys. Lett. B377 (1996) 147. [2] J. Gasser, M.A. Ivanov and M.E. Sainio, Nucl. Phys. B745 (2006) 84. [3] N. Kaiser, Nucl. Phys. A848 (2010) 198; Eur. Phys. J. A46 (2010) 373. [4] N. Kaiser and J.M. Friedrich, Eur. Phys. J. A36 (2008) 181. [5] N. Kaiser and J.M. Friedrich, Nucl. Phys. A812 (2008) 186.

Speaker: Prof. Norbert Kaiser (TUM)

Slides hadron2011nkaiser.pdf

3 Light-meson spectroscopy

I will review recent experimental developments and new results in the field of light meson spectroscopy.

Speaker: Sebastian Neubert (Technische Universität München)

Slides lmesons_neubert.pdf

4 Meson spectroscopy and resonances

Recent progress in the calculation of meson spectroscopy and resonances from lattice QCD will be discussed. Current challenges will be reviewed and a roadmap for future calculations will be presented.

Speaker: Dr Sinead Ryan (Trinity College Dublin)

Slides 3_SR-Hadron2011.pdf

5 Heavy-flavor mesons

New and recent results from B factories on conventional heavy flavor mesons will be presented, including properties of excited D and Ds mesons, new measurements of eta_c(nS) properties, the observation of h_b(nP) states and new precision measurements of bottomonium radiative and hadronic transitions

Speaker: Claudia Patrignani (University and INFN Genova)

Slides patrignani_HADRON2011_HeavyMesons.pdf

11:00 AM Coffee Break

Plenary Session: 2

Convener: Prof. Martin Faessler (LMU)

6 Latest developments in the spectroscopy of heavy hadrons

I discuss the recent developments in the heavy meson spectroscopy. Among the newly discovered states, I consider in particular the charmed mesons with strangeness and the puzzling meson X(3872), underlying strategies for their proper classification.

Speaker: Fulvia De Fazio (INFN Bari)

Slides defazio.pdf

7 The size of the proton

The charge radius Rp of the proton has so far been known only with a precision of about 1% from both electron scattering and precision spectroscopy of hydrogen. We have recently determined Rp by means of laser spectroscopy of the exotic "muonic hydrogen" atom [1]. Here, the muon, which is the 200 times heavier cousin of the electron, orbits the proton with a 200 times smaller Bohr radius. This enhances the sensitivity to the proton's finite size tremendously. Our new value Rp = 0.84184 (67) fm is ten times more precise than the generally accepted CODATA value, but it differs by 5 standard deviations from it. A lively discussion about possible solutions to the "proton size puzzle" has started. [1] R. Pohl, A. Antognini, F. Nez et al. (CREMA collaboration), "The size of the proton", Nature 466, 213 (July 2010)

Speaker: Randolf Pohl (Max-Planck-Institut für Quantenoptik)

Slides 2_Pohl_HADRON.pdf

8 The muonic hydrogen lamb shift and the definition of the proton radius

Recently the muonic hydrogen lamb shift has been measured with unprecedented accuracy [R. Pohl et al, Nature vol. 466, p. 213 (2010)], allowing for a precise determination of the proton radius. This determination is 5 sigma away from the previous CODATA value obtained from (mainly) the hydrogen lamb shift and the electron-proton scattering. Within an effective field theory formalism, I will define the proton radius and review the theoretical prediction for the muonic hydrogen lamb shift studying both the pure QED-like computation and the hadronic effects.

Speaker: Antonio Pineda (Universitat Autònoma de Barcelona)

Slides protonradius11.pdf

1:00 PM Lunch Break

Hadrons in Hot and Cold Medium: 1

Heavy ions, mesons in nuclei, and hypernuclei

Convener: Prof. Laura Fabbietti (TUM)

9 Weak decay of Lambda Hypernuclei

The information coming from the study of the Lambda-hypernuclei weak decay channels complements the knowledge of strange nuclear systems obtained by both missing mass and gamma-ray spectroscopy measurements. Lambda-hypernuclei decay through both the mesonic weak decay (MWD) and the non-mesonic weak decay (NMWD) processes. In particular, recently, the two-nucleon induced (2N) NMWD has been studied quite extensively both experimentally and theoretically. The FINUDA experiment performed a complete analysis of the charged particles (pi− and p) spectra following the MWD and NMWD of 5(Lambda)He, 7(Lambda)Li, 9(Lambda)Be, 11(Lambda)B, 12(Lambda)C, 13(Lambda)C, 15(Lambda)N and 16(Lambda)O hypernuclei. MWD spectra and decay rates have been obtained for 7(Lambda)Li, 9(Lambda)Be, 11(Lambda)B and 15(Lambda)N for the first time and compared with previous measurements and calculations. The spin-parity assignment for 15(Lambda)Ng.s. = 3/2+ was made for the first time and the results have been published [1]. The FINUDA Collaboration also analyzed the proton energy spectra of 5(Lambda)He, 7(Lambda)Li, 9(Lambda)Be, 11(Lambda)B, 12(Lambda)C, 13(Lambda)C, 15(Lambda)N and 16(Lambda)O with good resolution (deltap/p=2% FWHM for protons of 80 MeV) and with a detection threshold of 15 MeV. All measured spectra showed a similar behaviour, i.e. a bump at about 80 MeV, roughly at the energy expected from one-proton induced NMWD (with an incertitude of about 10 MeV due to several nuclear structure and interaction effects). The bump is quite well defined in the high energy portion, whereas at low energies it is blurred in a continuum generated by FSI, superimposed to the 2N-induced NMWD contribution. With very simple hypotheses and a model–independent method the contributions from FSI and 2N-induced NMWD were disentangled, providing a value of Gamma(2N)/Gamma(NMWD) of 0.24±0.10 [2]. This method was recently improved with the further detection of a neutron, from which we determined the value of Gamma(2N)/Gamma(NMWD) with an error reduced respect to the previous FINUDA determination [2]. The value is in agreement, within the errors, with previous evaluations, model dependent or not, and with theoretical calculations. Comparison of the FINUDA data with the available experimental results from KEK will be also presented. References: [1] M. Agnello et al., Phys. Lett. B 681 (2009) 139. [2] M. Agnello et al., Phys. Lett. B 685 (2010) 247.

Speaker: Dr Stefania Bufalino (INFN-TORINO)

Paper Proc_SBufalino.zip

Slides 1_SBufalino.pdf

10 First observation of the heavy hyper-hydrogen isotope 6ΛH

The replacement of a nucleon with a Λ hyperon leads to the production of Λ-hypernuclei. These strange systems are more stable than ordinary nuclei due to the compression of the nuclear core and to the addition of an extra binding energy from the Λ hyperon, which plays the so called “glue-like” role, being free from the Pauli blocking effect. In this respect, Λ-hypernuclei are better candidates than normal nuclei to exhibit large neutron excess and neutron halo phenomena. The study of hypernuclei with high N/Z values can give information on baryon-baryon interaction and on the behaviour of hyperons in a medium with a much lower density than for ordinary hypernuclei. Moreover the role of the three-body ΛNN force, related to the coherent Λ−Σ coupling, can be investigated. Great interest exists for the possible existence of 6ΛH (N/Z=4). Theoretical calculations [1] predict the existence of a stable single-particle state with a binding energy of 5.8 MeV from the 5H + Λ threshold when the Σ−Λ coupling is considered, while without this term the state would be very close to the 4ΛH + 2n threshold, with a binding energy of 4.4 MeV, as initially predicted by Majling [2]. Production rates have not yet been evaluated theoretically. Experimentally, 6ΛH can be produced by the two-step Double Charge Exchange (DCX) mechanism: K- + p --> Λ + π0; π0 + p --> n + π+ on a 6Li target. The experimental observation of the production of such a neutron-rich hypernucleus would be the most evident example of the glue-like role of the Λ hyperon, being the 5H core above the 3H+2n emission threshold. The FINUDA experiment, dedicated to the study of spectroscopy and decay of Λ-hypernuclei produced by means of the (K-stop, π-) Strangeness Exchange reaction at DAΦNE, the INFN Frascati φ-factory, studied the production of 6ΛH: with a partial data sample an upper limit of (2.5+-0.4) 10-5/K-stop at 90% C.L. [3] was obtained by analyzing the DCX π+ momentum. Considering the final data sample of the experiment it is now possible to perform a more accurate identification of the production, by requiring the coincidence of the π- coming from the mesonic decay of the hypernucleus: three events have been observed which can be attributed to the 6ΛH hypernucleus production and decay. The hypernuclear mass evaluated from the events is ~5801.4 MeV/c2, which would indicate the absence of a significant Λ−Σ coupling term contribution. The production rate is actually under evaluation: the preliminary indication is of the order of 10-6/K-stop. This is the first observation of 6ΛH. [1] Y. Akaishi, T. Yamazaki, Frascati Physics Series XVI (1999) 59. K.S. Myint et al., Few-Body Sys. Suppl. A 12 (2000) 383. [2] L. Majling, Nucl. Phys. A 585 (1995) 221c. [3] M. Agnello et al., Phys. Lett. B 640 (2006) 145.

Speaker: Prof. Elena Botta (INFN-Sezione di Torino and Universita’ di Torino)

Paper botta.gz

Slides 2_Hadron11_BottaE.pptx

11 Kaonic 3He and 4He X-ray measurements in SIDDHARTA

An energy shift of the 2p level of kaonic 3He and 4He atoms is recently studied in theory and experiment. A theory predicting deeply bound kaonic nuclear states estimates a significant energy shift in kaonic 3He or 4He. The SIDDHARTA experiment measured the kaonic 3He and 4He 3d-2p X-ray transitions at the DAFNE e+e- collider. The strong interaction shifts of the kaonic 3He and 4He 2p state were determined precisely. The world's first observation of kaonic 3He was performed. In addition, a possible isotope effect between 3He and 4He was obtained. In this talk, the results of kaonic 3He and 4He X-ray measurements in the SIDDHARTA experiment will be presented, as well as future plans.

Speaker: Dr Tomoichi Ishiwatari (Stefan-Meyer-Institut fuer subatomare Physik)

Slides Hadron11-ishiwatari.pdf

12 A new measurement of kaonic hydrogen X-rays

The SIDDHARTA collaboration have measured the K-series x-rays of kaonic hydrogen atoms with significant improvements over the previous experiments, and precisely determined the strong-interaction energy-level shift and width of the 1s atomic state. The measurement offers a unique possibility to determine the KN s-wave scattering lengths, which is one of the most important observable to investigate chiral SU(3) dynamics in low-energy QCD and the role of explicit chiral symmetry-breaking due to the relatively large strange quark mass. It is also strongly related to recent hot topics of the structure of the Lambda(1405) resonace and possible deeply bound kaonic systems. The result will set tight constraints on those theories. The experiment has been performed at the DAFNE e+e- collider which produces the phi-resonance that decays into K+K-. The resulting low energy K-'s with small energy spread are well suited to be stopped in a gas target efficiently for producing these atoms. As x-ray detectors, we employed novel large-area silicon drift detectors having higher energy and timing resolution than in previous experiments, which were developed especially for this experiment. In this talk, our final results on kaonic hydrogen will be presented, and future plans will be as well discussed.

Speaker: Dr Shinji Okada (LNF-INFN)

Paper 20110901_1800_hadron2011proc_submit.tgz

Slides Hadron2011_Shinji_Okada.pdf

Heavy Hadrons: 1

Spectroscopy and decay of heavy hadrons

Convener: Dr Alberto Correa dos Reis (Centro Brasileiro de Pesquisas Fisicas)

13 The role of final-state interactions in Dalitz plot studies

Dalitz plot studies for multi-hadron decays of heavy mesons are expected to become very important tools for precision investigations of CP violation. A thorough understanding of the hadronic final-state interactions is a prerequisite to achieve a highly sensitive, model-independent study of CP-violating phases in such processes. I will illustrate the theoretical tools available, as well as still to be developed, from low-to-medium-energy hadron physics for this purpose, and the goals of the informal "Les Nabis" network studying these and related problems.

Speaker: Dr Bastian Kubis (Universität Bonn)

Slides Kubis_Hadron2011_MUC.pdf

14 Three-body Final State Interaction in $D^+ \rightarrow K^- \pi^+ \pi^+$ and Its effect on the $K\pi$ phase shift

The last decade provided important advances on light scalar resonances sector in the D decays. In particular, different analyses showed the evidence for $\sigma$ and $\kappa$ mesons close to the threshold. Decays of charmed meson, however, are still poorly understood theoretically. The $K^-\pi^+$ phase shift extracted from $D^+\to K^- \pi^+\pi^+$[1] and from $K^-\pi^+$ scattering[2] are significantly different. Our main purpose is to understand this discrepancy. We investigate $D^+\to K^- \pi^+\pi^+$ exploring two gaps in the theoretical models. The first one is the weak vertex, which we know very little about. The other is the final state interactions. We focus our work on the low energy part of $K\pi$ spectrum making two assumptions: the contribution of $\pi^+\pi^+ $ interaction is small and can be neglected; the $K$ interacts with only one pion at a time. The basic building block in the calculation is a $K\pi$ amplitude based on unitarized chiral perturbation theory[3], and with parameters determined by a fit to elastic LASS data. For the weak vertex, three different topologies are considered. The perturbative solution involve the sum of diagrams with different numbers of loops. We found that each term in this series is systematically related to the previous one and a ressummation of the whole series was performed. The analysis shows that corrections to the ressummed series are important at threshold and converge rapidly at higher energies. The interference of the different contributions in the whole amplitude change the phase shift. Two classes of weak vertices reproduce the scattering phase shift from LASS[2], whereas the third one describe the behaviour of $K^- \pi^+$ phase shift from FOCUS[1] in the elastic range. This result suggests a dominant decay mechanism in the $D^+ \rightarrow K^- \pi^+ \pi^+$. _________________________________________________________ [1] J.M. Link {\it et al.} [FOCUS Collaboration], Phys.\ Lett.\ B {\bf 653}, (2007) 1; J.M. Link {\it et al.} [FOCUS Collaboration], Phys.\ Lett.\ B {\bf 681}, (2009) 14; [2]D. Aston {\it et al.}, Nucl. Physc. {\bf B 296} (1988) 493. [3] G. Ecker, J. Gasser, A. Pich and E. De Rafael, Nucl. Phys. B{\bf 321}, 311 (1989); J.A. Oller and E. Oset, Nucl. Phys. A {\bf 620}, 438 (1997); M. Jamin, J.A. Oller, A. Pich, Nucl. Phys. {\bf B 587} (2000) 331.

Speaker: Ms Patricia Magalhães, C. (University of São Paulo, Brazil)

Slides 2_Magalhaes_Hadron2011.pdf

15 eta - eta prime Mixing - From electromagnetic transitions to weak decays of charm and beauty hadrons

It has been realized for a long time that knowing the eta and eta^prime wave functions in terms of quark and gluon components probes our understanding of non-perturbative QCD dynamics. Great effort has been given to this challenge -- yet no clear picture has emerged even with the most recent KLOE data. We point out which measurements would be most helpful in arriving at a more definite conclusion. A better knowledge of these wave functions will significantly help to disentangle the weight of different decay subprocesses in semi-leptonic decays of D+, Ds^+ and B+ mesons. The resulting insights will be instrumental in treating even non-leptonic B transitions involving eta and eta^prime and their CP asymmetries; thus they can sharpen the case for or against New Physics intervening there.

Speaker: Dr camilla di donato (INFN Sez. Napoli)

Paper http://arxiv.org/abs/1109.0268

Slides EtaEtapHadron11.pptx

16 Studies of the X(3872) as a mixed molecule-charmonium state in QCD Sum Rules

Abstract: We use QCD sum rules to investigate the nature of the meson X(3872), assumed to be a mixture between charmonium and exotic molecular c bar{q}[q\bar{c}]$ states with J^{PC}=1++. We compute the mass of the state, decay widths of the channels J/psi(npi) and J\psi\gamma, and the branching ratio for the production of the state in the decay B to X(3872)K. We find that the results are compatible with the experimental data for a small range for the values of the mixing angle, 5^\circ\leq\theta\leq13^\circ.

Speaker: Dr Carina M. Zanetti (Instituto de Física, USP)

Paper contribution.zip

Slides 4_zanetti-hadron11.pdf

Light Baryons: 1

Spectroscopy and structure (formfactors, parton distributions functions, spin) of light baryons

Convener: Dr Elke-Caroline Aschenauer (Brookhaven Natl. Lab. (BNL))

17 Overview on CLAS baryon results

Nucleons are complex systems of confined quarks and exhibit characteristic spectra of excited states. Highly-excited nucleon states are sensitive to details of quark confinement which is poorly understood within Quantum Chromodynamics (QCD), the fundamental theory of strong interactions. Observing and understanding these higher-mass resonances is crucial, but they are difficult to observe since they are broad and overlapping. Very often, these higher-lying states reveal themselves more clearly through interference with dominant amplitudes. These interference terms can be isolated via polarization observables. At Jefferson Lab, extensive data sets on photo- as well as electro-production of pseudo-scalar mesons ($\pi$, 2$\pi$, $\eta$, K) and vector mesons ($\rho$, $\omega$, $\phi$) have been accumulated over the last few years using the CEBAF Large Acceptance Spectrometer (CLAS). The current efforts with CLAS focus on utilizing highly-polarized hydrogen and deuterium targets in combination with polarized photon beams toward a complete measurement of a large number of reaction channels. In particular, the CLAS g9a (FroST) experiment, as part of the $N^\ast$ program at Jefferson Laboratory, has accumulated photoproduction data using linearly- and circularly-polarized photons incident on a longitudinally-polarized butanol target in the energy range 0.3 to 2.4 GeV. This contribution discusses recent results on (mostly) single- and double-pion photoproduction.

Speaker: Volker Credé (Florida State University)

Slides 1_talk_hadron11.pdf

18 Measurement of the double polarisation observable G in the reactions \vec{\gamma} \vec{p} \to p \pi^0 and \vec{\gamma} \vec{p} \to p \eta

The excitation spectrum of the nucleon consists of several overlapping resonances. To identify these resonances, and their contributions to the measured cross sections, a partial wave analysis is used. One needs at least a set of eight, well chosen, single and double polarisation observables to give an unambiguous solution. With the Crystal Barrel/TAPS setup at ELSA, single and double polarisation observables can be measured, by using a combination of a linearly or circularly polarised photon beam and a longitudinally or transversely polarised butanol frozen spin target. In this talk the results of the measurement of the double polarisation observable G in the reactions \vec{\gamma} \vec{p} \to p \pi^0 and \vec{\gamma} \vec{p} \to p \eta are presented. This pro ject is supported by the DFG (SFB/TR16).

Speaker: Marcus Gruener (Helmholtz-Institut für Strahlen- und Kernphysik)

Slides 2_Talk-Gruener-Hadron11n.pdf

19 Measurement of the double polarisation observable E in \pi^0 and \eta photoproduction

One of the open challenges in subnuclear physics is to understand the nonperturbative regime of Quantum chromodynamics, including the world of the nucleon and its excitations. In order to extract the contributing baryon resonances in photoproduction experiments, partial wave analyses need to be performed. A complete experiment is required to unambiguously determine the contributing amplitudes. This involves the measurement of carefully chosen single and double polarisation observables. With the Crystal-Barrel/TAPS experiment at ELSA measurements of polarisation observables are possible for different reactions by using a circularly or linearly polarised photon beam and a longitudinally or transversely polarised frozen spin butanol target. The Crystal-Barrel/TAPS setup provides a nearly 4\pi angular coverage, a good energy resolution, and a high detection efficiency for photons and is therefore ideally suited to study final states comprising neutral mesons. In this talk results for the measurement of the double polarisation observable E in the reactions \vec{\gamma} \vec{p} \to p \pi^0 and \vec{\gamma} \vec{p} \to p \eta will be presented. Supported by the DFG (SFB/TR16).

Speaker: Jonas Müller (Universität Bonn)

Slides 3_hadron2011_jonasmueller.pdf

Light Mesons: 1

Spectroscopy and decay of light mesons

Convener: Dr Wolfgang Ochs (research scientist)

20 The nature of the lightest scalar meson, its Nc behavior and semi-local duality

The leading $1/N_c$ behaviour of Unitarised Chiral Perturbation Theory distinguishes the nature of the $\rho$ and the $\sigma$. At one loop order the $\rho$ is a ${\bar q}q$ meson, while the $\sigma$ is not. However, semi-local duality between resonances and Regge behaviour cannot be satisfied for larger $N_c$, if such a distinction holds. While the $\sigma$ at $N_c=3$ is inevitably dominated by its di-pion component, Unitarised Chiral Perturbation Theory beyond one loop order reveals that as $N_c$ increases above 6-8, the $\sigma$ has a sub-dominant ${\bar q}q$ fraction up at 1.2 GeV. Remarkably this ensures semi-local duality is fulfilled for the range of $N_c \lesssim 15$, where the unitarisation procedure adopted applies.

Speaker: Dr Jose R. Pelaez (Universidad Complutense)

Paper jrpelaezcontribution.tar.gz

Slides 1_JRPelaez-Hadron_2011.ppt

21 Study of Light Scalars, the learned Lessons

The light scalar meson problem which has arisen 50 years ago from the linear sigma model ( LSM), became central in the nonperturbative QCD since LSM could be its low energy realization. The scalar channels in the region up to 1 GeV is a stumbling block of QCD. The point is that not only perturbation theory fails here, but sum rules as well in view of the fact that isolated resonances are absent in this region. Attention is paid to the production mechanisms of light scalars that reveal their nature. It is revealed the chiral shielding of the \sigma(600) meson and shown that the \sigma field is described by its four-quark component in the \sigma resonance energy (virtuality) region. The \pi\pi scattering amplitude with regular analytical properties in the s complex plane is constructed taking into account the chiral shielding of the \sigma (600) meson and its mixing with the f_0(980) meson.The data agrees with the four-quark nature of the \sigma (600) and f_0(980) mesons. The amplitude in the range -5 m_\pi^2 < s < 0.64 GeV^2 also agrees with results, obtained on the base of the chiral expansion, dispersion relations, and the Roy equations. It is shown that the kaon loop mechanism of the \phi radiative decays, ratified by experiment, is the four-quark transition and points to the four-quark nature of light scalars. It is shown also that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor q\bar q mesons that are produced via two-quark transitions \gamma\gamma\to q\bar q. A programme of further investigations is laid down.

Speaker: Prof. Nikolay Achasov (Sobolev Institute for Mathematics)

Slides Achasov_Talk_HADRON_2011.pdf hadron2011.zip

22 Measurement of meson-photon transition form factors with the BABAR detector

Two-photon processes can be studied at e+e- colliders via the reaction e+ e- -> e+ e- gamma gamma(*) -> e+ e- X, providing a suitable environment for hadron spectroscopy and tests of QCD predictions. We report recent measurements of the gamma gamma* -> P transition form factors at large values of momentum transfer -- where P is a pseudoscalar meson: pi0, eta, eta', and eta_c -- performed in analyses of high luminosity data collected at the PEP-II collider with the BABAR detector.

Speaker: Prof. Evgeny Solodov (Budker INP)

Slides 3_solodov_gg_hadron2011.pdf

23 Recent results on hadrons via Initial State radiation at BABAR

We report on latest results obtained at BABAR studying low energy e+e- annihilations, produced via initial state radiation. Hadronic cross sections are the experimental input for calculation of the muon anomalous magnetic moment, while the study of the final states and intermediate structures with unprecedented accuracy can reveal new states and their properties. In particular, an updated measurement, using the total data set taken by BABAR, of the cross sections for e+e- -> h+h-h'+h'- (where h,h'=pi,K), and of the study of the Y(2175) --> phi f_0(980) resonance, will be presented.

Speaker: Prof. Evgeny Solodov (Budker INP)

Slides 4_Solodov_HADRON2011.pdf

4:00 PM Coffee Break

Heavy Hadrons: 2

Spectroscopy and decay of heavy hadrons

Convener: Prof. Hal Evans (Indiana Univ.)

24 A comprehensive interpretation of the D_{sJ} states

The leading order interaction between a Goldstone boson and a matter field is universally dominated by the Weinberg-Tomozawa term. Based on this observation, we predict a rich spectrum of bound states of a kaon and a heavy meson. We argue that if the life time of an excited heavy meson is significantly longer than the range of forces, then the finite width of that state can be neglected in a first approximation. Then, the $D_{s0}^*(2317)$, $D_{s1}(2460)$, $D_{sJ}(2860)$ and $D_{sJ}(3040)$ are generated as $DK$, $D^*K$, $D_1(2420)K$ and $D^*(2600)K$ bound states, respectively. Except for the remarkable agreement with the measured masses, the decay patterns of the $D_{sJ}(2860)$ and $D_{sJ}(3040)$ can also be understood. Two more $D_{sJ}$ states, and kaonic bound states with the bottom mesons as well as the doubly charmed baryon are also predicted.

Speaker: Dr Feng-Kun Guo (Universität Bonn)

Paper HADRON2011_Guo.ZIP

Slides DsJ.pdf

25 A new interpretation for the $D^*_{s2}(2573)$ and the prediction of novel exotic charmed mesons

We study the vector - vector interaction within the hidden gauge formalism in a coupled channel unitary approach. In the sector $C=1,S=1,J=2$ we get a pole in the T-matrix around $2572$ MeV that we identify with the $D^*_{s2}(2573)$, coupling strongly to the $D^*K^*$($D^*_s\phi$($\omega$)) channels. In addition we obtain resonances in other exotic sectors which have not been studied before such as $C=1,S=-1$, $C=2,S=0$ and $C=2,S=1$. This 'flavor-exotic' states are interpreted as $D^*\bar{K^*}$, $D^*D^*$ and $D^*_sD^*$ molecular states but have not been observed yet. In total we obtain nine states with different spin, isospin, charm and strangeness of non $C=0,S=0$ and $C=1,S=0$ character, which have been reported before.

Speaker: Mrs Raquel Molina (IFIC)

Paper proc_exotic.tar.gz

Slides 3_exotics.pdf

26 D and D_s meson spectroscopy from lattice QCD

We present results for the low-lying spectrum of D and D_s mesons from a lattice QCD calculation on 2+1 flavor Clover-Wilson configurations generated by the PACS-CS collaboration. In particular S- and P-wave states of charmed and charmed-strange mesons are explored for pion masses down to 156MeV. For the heavy quark, the Fermilab method is employed. In addition to ground states, some excited states are extracted using the variational method. To check our setup, calculations of the charmonium spectrum are also carried out. For charmonium, the low-lying spectrum agrees favorably with experiment. For heavy-strange and heavy-light systems substantial differences in comparison to experiment values remain in channels with nearby scattering states.

Speaker: Dr Daniel Mohler (TRIUMF)

Slides hadron2011.pdf

27 The physics potential of SuperB

The large samples of B, D and tau decays that will be recorded at SuperB can be used to provide both stringent constraints on new physics scenarios, and overconstraints on the Standard Model. We discuss the physics potential what can be learned from SuperB.

Speaker: Dr Fergus Wilson (Rutherford Laboratory)

Slides SuperB.pdf

Light Baryons: 2

Spectroscopy and structure (formfactors, parton distributions functions, spin) of light baryons

Convener: Prof. Reinhard Beck (Univ. Bonn)

28 Baryon Spectroscopy at COMPASS

COMPASS is a fixed-target experiment at CERN SPS which investigates the structure and spectroscopy of hadrons. The experimental setup features a large acceptance and high momentum resolution spectrometer including particle identification and calorimetry and is therefore ideal to cover a broad range of different topics. During in total 9 weeks in 2008 and 2009, a 190 GeV/c proton beam impinging on a liquid hydrogen target was used primarily to study the production of exotic mesons and glueball candidates at central rapidities. As no bias on the kinematics of the forward-going particles was introduced by the trigger system, these data also yield the unique possibility to study diffractive dissociation of the beam proton. The recoiling target proton remains intact in this peripheral scattering process. Exclusive events with one proton and either a pair of oppositely charged pions or kaons in the final state have been extracted and dominant features of the light baryon spectrum became clearly visible. We will present the status of the ongoing studies and discuss the usage of partial-wave analysis techniques, which are successfully applied already for diffractive dissociation reactions of pions in COMPASS.

Speaker: Mr Alexander Austregesilo (TU München)

Slides austregesilo_20110613.pdf

29 Photoproduction of η-Mesons off Light Nuclei

Recent experiments at the Mainz MAMI and the Bonn ELSA accelerators have studied the excitation spectrum of the nucleon with photoproduction of η-mesons off light target nuclei (2H, 3He). Special attention was given to the photoexcitation of the neutron in order to investigate the isospin structure of electromagnetic resonance couplings. The resulting cross sections shows a narrow in the reaction on the neutron, which is not visible on the proton. This structure was first seen in measurements of the GRAAL-, CBELSA-, and LNS-Sendai collaboration. Recent results of the Mainz A2-collaboration which confirm this structure in new high statistics measurements will be presented. The structure appears in the measurements off neutrons bound in deuterium or 3He in the same way, which makes specific nuclear effects very unlikely. Additionally few nucleon systems as 3He have been used for the investigation of the meson-nucleon and meson-nucleus interactions. Recent results for coherent η-photoproduction off 3He confirm the strong threshold enhancement of this reaction reported from an earlier experiment by M. Pfeiffer et. al. (Phys. Rev. Lett. 92 (2004) 252001) with much better statistical quality. This behaviour gives further evidence for the possible formation of a quasi-bound η nulceus state.

Speaker: Ms Lilian Witthauer (Basel University, Department of Physics)

Slides witthauer_Hadron11_v0.pdf

30 A case for new narrow nucleon resonance

We review recent evidences for putative narrow nucleon N$^*$(1685)-- the candidate for the non-strange member of the exotic anti-decuplet of baryons.

Speaker: Prof. Maxim Polyakov (Ruhr University Bochum)

Slides 3_Polyakov_H11.pdf

31 Single and Double Pion Photoproduction off the Deuteron

Meson photoproduction allows a detailed investigation of the excitation spectrum of the nucleon and of the interactions of mesons with nucleons and nuclei. Up to now much more attention has been paid to the electromagnetic excitations of the free proton than to its neutron counter parts. These are essential for the understanding of their isospin decomposition. In addition in certain states the electromagnetic coupling of photons to protons is rather different from that to neutrons. So far the sole experimental possibility to investigate this subject is the quasi-free photoproduction of mesons off neutrons bound in nuclei, in particular in the deuteron. As a consequence the production cross section will of course be influenced by nuclear Fermi motion and potentially also by nuclear final state interaction effects (FSI). However, such effects can be studied by a comparison of the free proton cross section to the quasi-free cross section measured in coincidence with recoil protons. In the last few years, the photoproduction of mesons off the deuteron were studied with the Crystal Barrel/TAPS setup at the ELSA accelerator in Bonn and the Crystal Ball/TAPS setup at the MAMI accelerator in Mainz. We will report some of the most interesting results of single and double pion photoproduction, i.e. $\pi^{0}$, $\pi^{0}\pi^{0}$, $\pi^{0}\pi^{\pm}$, off quasi-free protons and neutrons.

Speaker: Manuel Dieterle (Basel University, Department of Physics)

Slides dieterle_hadron_0611.pdf

32 Study of psi' --> ppbar eta at BESIII

Based on 106×10^6 psi' events collected with BESIII at the BEPCII, the decay of psi'--> ppbar eta is studied. The exicted baryon N(1535) is clearly observed and the results from PWA are presented.

Speaker: Mr Xiaotao LIAO (Institute of High Energy Physics)

Paper liaoxt_proceeding_hadron2011.zip

Slides 5_liaoxtHadron2011.pdf

Light Mesons: 2

Spectroscopy and decay of light mesons

Convener: Prof. Wolfgang Dünnweber (Univ. München)

33 Central Meson Production in ALICE

R. Schicker for the ALICE Collaboration The ALICE experiment at the Large Hadron Collider (LHC) at CERN consists of a central barrel covering the pseudorapidity range -0.9 < eta < 0.9 and of additional detectors which can be used to define pseudorapidity gaps -3.7 < eta < -0.9 and 0.9 < eta < 5.1. The low pT threshold of the central barrel gives ALICE a unique opportunity to study the low mass sector of central production at the LHC. I will report on first analysis results of meson production in double gap events in proton-proton collisions at sqrt{s} = 7 TeV and in PbPb collisions at sqrt{s(NN)} = 2.76 TeV.

Speaker: Dr Rainer Schicker (Phys. Inst.)

Slides schicker_hadron2011.pdf

34 Glueballs from gluon jets at the LHC

The existence of glueballs within QCD is uncontroversial but their experimental verification is still in doubt. We discuss the new possibilities for a search of glueballs as the leading object in gluon jets at the LHC and also recall previous results from LEP.

Speaker: Dr Wolfgang Ochs (research scientist)

Slides lhcmuc.pdf

35 Structure of scalar mesons and the Higgs sector of strong interaction

The scalar mesons sigma(600), kappa(800), f0(980) and a0(980) together with the pseudo Goldstone bosons pi, K and eta may be considered as the Higgs sector of strong interaction. After a long time of uncertainty about the internal structure of the scalar mesons there now seems to be consistency which is in line with the major parts of experimental observations. Great progress has been made by introducing the unified model of Close and Törnqvist [1]. This model states that scalar mesons below 1 GeV may be understood as tetraquarks in S-wave with some qbarq in P-wave. Further out they rearrange as meson-meson states. We show that the P-wave component inherent in the structure of neutral scalar mesons can be understood as doorway state for the formation of the scalar meson via two-photon fusion, whereas in nucleon Compton scattering these P-wave components serve as intermediate states of the scattering process [2]. Explicit expressions for the flavour structure of the qbarq states are derived and it is shown that these flavour structures are consistent with the two-photon widths of the scalar mesons. The masses of the scalar mesons are predicted in terms of spontaneous and explicit symmetry breaking. Spontaneous symmetry breaking leads to the same mass for all scalar mesons being 652 MeV. Explicit symmetry breaking increases the masses of the scalar mesons by an amount which depends on the fraction of strange and/or anti-strange quarks in the scalar meson. The Goldstone bosons showing up as part of the spontaneous symmetry-breaking process as mass-less particles acquire mass due to explicit symmetry breaking. This mass is absorbed into the mass of the scalar meson and in this way contributes to explicit symmetry breaking. Good agreement is obtained between the experimental and predicted masses of the scalar mesons. A comparison between spontaneous symmetry breaking in strong and EW interaction is given. [1] F.E. Close and N.A. Törnqvist, J. Phys. G: Nucl. Part. Phys. 28 R249 (2002), arXiv:hep-ph/0204205. [2] M. Schumacher, Eur. Phys. J. C 67, 283 (2010), arXiv:1001.0500 [hep-ph].

Speaker: Prof. Martin Schumacher (Zweites Physikalisches Institut der Universität Göttingen)

Paper arXiv.org>hep-ph>arXiv:1107.4226

Slides hadron11.pdf

36 Finite volume effects in the meson scalar sector and generalization of Luescher approach to two coupled channels

We develop a scheme on how to obtain the lightest scalar mesons from hypothetical QCD lattice results. The latter are simulated by using the two channel chiral unitary approach for and K Kbar scattering that generates the f0(600) and f0(980) resonances. We re-derive Luescher formula for one channel in a very simple way suited to practitioners of the chiral unitary approach, and then from the finite volume discrete eigenenergies we induce the free scattering amplitude using the one channel Luescher formula, which we show to work remarkably well up to energies very close to the K Kbar threshold. We then propose some methods to extend Luescher results to two channels and find that they work and allow us to obtain results for the different coupled channel amplitudes beyond the K Kbar threshold. With the two channel method we find that one can obtain in a clean way both the f0(600) and f0(980) resonances of the scalar sector in I = 0 and the a0(980) in I = 1 with the and K Kbar channels. An error analysis is done to determine the precision needed in the lattice calculations.

Speaker: Eulogio Oset (IFIC , University of Valencia)

Slides 4_finitevolume.pdf

Quarkonia: 1

Production, spectroscopy, and decay of quarkonia

Convener: Prof. Miriam Fritsch (Univ. Mainz)

37 Measuring the phase between strong and EM J/psi decay amplitudes

Experimental data in various channels show that in $J/\psi$ decay, strong and electromagnetic amplitudes seem to be orthogonal, while in the standard model they are expected to be both almost real. There has been the conjecture that the phase between strong and electromagnetic amplitudes is universally $-90^\circ$ in all decays of charmonium (quarkonium) $1^{--}$ states. However, so far the determination of this phase has been based mostly on theoretical assumptions about SU(3) symmetry. We propose to measure this phase directly by the scan of the energy region below the charmonium $1^{--}$ resonances. We present the theoretical basis of such measurement and analyze the feasibility and sensitivity for the data to be eventually taken by BES-III experiment.

Speaker: Prof. Marco Maggiora (INFN Torino)

Paper Proceedings tarball as submitted to arxiv.

Slides HADRON2011.Maggiora.JPsi_scan.pdf

38 Study of charmonium decays at BESIII

In this talk, we will present the results on the charmonium decays with the $J/\psi$ and $\psi^\prime$ data samples collected with the BESIII experiments at the BEPCII collider. With the world largest data samples at these two peaks, we observed for the first time many new decay modes of $J/\psi$, $\psi^\prime$, $\chi_{cJ}$, and $\eta_c$, we also improve the precisions of the branching fractions of some other decay modes.

Speaker: Mr Jifeng HU (Graduate University of Chinese Academy of Sciences)

Slides 2_hadron2011muchen_hjf.pdf

39 Study of charmonium spectroscopy at BESIII

In this talk, we will present the results on the charmonium spin singlet states below the open charm threshold, including $h_c$, $\eta_c$, and $\eta_c(2S)$. The masses, widthes, and production rates of these states will be reported. The results are based on a data sample of 106 million $\psi^\prime$ events collected with the BESIII experiments at the BEPCII collider.

Speaker: Dr Liangliang WANG (Institute of High Energy Physics)

Paper proceeding_hadron2011.zip

Slides 3_CharmoniumSpectAtBes3_wangll.pdf

40 Microscopic Model of Charmonium Strong Decays

Meson strong decay is a complex non-perturbative process that has not been described from QCD first principles yet. Instead, several phenomenological models have been developed to deal with this topic, being the 3P0 [1], the flux-tube [2] and the Cornell [3, 4] models the most popular. To address a more fundamental description of the decay mechanism, one has to describe hadron strong decays in terms of quark and gluon degrees of freedom. However, there has been little previous work in this area. Two different examples are the study of open-charm decays of charmonium resonances by Eichten et al. [3], who assumed that decays are due to pair production from the static part of a Lorentz vector confining interaction, and the study of a few strong decays in the light sector by Ackleh et al. [4], who assumed that the quark-antiquark pair production comes from one-gluon exchange and a scalar confining interaction. Following Ref. [4] for the development of a microscopic model, the strong decays are driven by the same interquark Hamiltonian which determines the spectrum given by the one-gluon exchange and the confining interaction. These interactions and their associated decay amplitudes are undoubtedly all present and should be added coherently. Our constituent quark model (CQM) [5] for the heavy quark sector has a one-gluon exchange term and a mixture of Lorentz scalar and vector confining interactions. This completely defines our microscopic model for strong decays. Unlike previous works we use a screening confinement interaction and also a mixture between scalar and vector Lorentz structures, which is already fixed. The wave functions for the mesons involved in the reactions are the solutions of the Schrödinger equation. Our results are in reasonable agreement with the predictions obtained by a 3P0 model. We obtain a total decay width of 19 MeV for the psi(3770) resonance in a parameter free calculation which agrees with the experimental data. Other decays of charmonium states will be presented. [1] L. Micu, Nucl. Phys. B 10, 521 (1969). [2] R. Kokoski and N. Isgur, Phys. Rev. D 35, 907 (1987). [3] E. Eichten, K. Gottfried, T. Kinoshita, K.D. Lane and T. M. Yan, Phys. Rev. D 17, 3090 (1978); 21, 203 (1980). [4] E.S. Ackleh, T. Barnes and E.S. Swanson, Phys. Rev. D 54, 6811 (1996). [5] J. Vijande, F. Fernandez and A. Valcarce, J. Phys. G 31, 481 (2005). [6] J. Segovia, A.M. Yasser, D.R. Entem and F. Fernandez, Phys. Rev. D 78, 114033 (2008).

Speaker: Mr Jorge Segovia (University of Salamanca)

Paper ID53_Segovia.tar.gz

Slides 4_JSegovia_strong_HADRON2011.pdf

41 Does the I = 1 State exist in c cbar meson?

Hiroshi Noya Institute of Physics, Hosei University at Tama Machida, Tokyo 194-0298, Japan e-mail : hiroshinoya@yahoo.com and Hiroshi Nakamura Department of Physics and Mathematics, College of Science and Engineering Aoyamagakuin University, Fuchinobe, Sagamihara, Kanagawa 229-8558, Japan We present the mass formula of the Diquark Cluster Model (DCM) to calculate the q２qbar2 system for the c cbar mesons with the u, d, s and c quarks. All parameters in the mass formula are already fixed to the analyses of the mass spectrum for the meson 1) except for c quark mass and related spin parameters. Using the Charmed baryons mass, we obtained these parameters. We calculated the mass of X(3945) to X(4660) c cbar mesons. The difference between the calculated mass and the experimental ones are less than 40 Mev. The following examples are our results. c n cbar nbar configurations. X(4260) : 4259 MeV. ; Exp. : 4263 MeV. X(4430) : 4407 MeV. ; Exp. : 4443 MeV. c s cbar sbar configuration. X(4350) : 4334 MeV. ; Exp. : 4350 MeV. From our calculation, we conclude that the X (3940) to X (4660) c cbar mesons is the four quark states. 1) Y.Uehara, N.Konno, H.Nakamura and H.Noya: Nucl. Phys. A606 (1996) 357

Speaker: Dr Hiroshi Noya (Institute of Physics, Hosei University at Tama)

Slides 5_Presentation.pptx

6:10 PM Welcome reception

Tuesday, June 14

Plenary Session: 3

Convener: Prof. Marek Karliner (Tel Aviv University)

42 Nucleon spin and parton distribution functions

In the Quark Parton Model, the nucleon is successfully described in terms of parton distribution functions (PDFs). Whereas unpolarized parton distributions like $q(x)$ and $g(x)$ interpreted as number densities of quarks and gluons at a given longitudinal momentum fraction $x$ in the nucleon are relatively well known, distribution involving polarization degrees of freedom are less well known. The most prominent ones, related to the nucleon spin problem, are the helicity distributions $\Delta q(x)$, $\Delta G(x)$ and the transversity distributions $\Delta q_T(x)$. The picture of the Quark Parton Model can be extended if in addition transverse momenta or the transverse position of partons inside the nucleon are considered. This leads to the introduction of transverse momentum distributions (TMDs) and generalized parton distributions (GPDs), respectively. An overview of recent experimental results and future plans will be given.

Speaker: Joerg Pretz (Universitaet Bonn)

Slides jpretz_hadron11.pdf

43 The 3-dimensional momentum structure of the nucleon

Recently, the exploration of the partonic composition of protons and neutrons has entered a new phase, with the study of the three-dimensional momentum and space structure. New theoretical concepts like the Transverse Momentum Dependent Distributions (TMDs) help to describe the momentum distributions of partons inside nucleons. Several dedicated experiments are running, being built or planned. A short review of the latest results and progress on TMDs, is presented.

Speaker: Mauro Anselmino (Università degli Studi di Torino)

Slides Munich-June.pdf

44 Light-baryon spectroscopy

One of the open challenges in subnuclear physics is to understand the non-perturbative regime of Quantum Chromodynamics, including the world of the nucleon and its excitations. One of the key issues here is to identify the relevant degrees-of-freedom and the effective forces between them. A necessary step towards this aim is a precise knowledge of the experimental spectrum and the properties of baryon resonances. Light baryon resonances are investigated by several experiments worldwide. In the presentation, among other results recent double polarisation experiments at ELSA, JLAB and MAMI will be discussed.

Speaker: Reinhard Beck (Rheinische Friedrich-Wilhelms-Universität Bonn)

45 Hadron structure, baryon and meson form factors, g-2

Lattice simulations of hadronic structure are now reaching a level where they are able to not only complement, but also provide guidance to current and forthcoming experimental programmes. In this talk I will discuss recent progress that has been made in this area, focussing on the electromagnetic form factors of the nucleon and the pion, the nucleon axial charge and the vacuum polarisation contribution to g-2.

Speaker: James Zanotti (University of Edinburgh)

Slides 4_Zanotti.pdf

11:00 AM Coffee Break

Plenary Session: 4

Convener: Prof. Claude Amsler (University of Zurich)

46 The Quest for the Spin of the proton - Results from RHIC

A myriad of new techniques and technologies made it possible to inaugurate the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory as the world's first high-energy polarized proton collider in December 2001. RHIC delivers polarized proton-proton collisions at a center of mass energies of up to 500 GeV. This unique environment provides opportunities to study the polarized quark and gluon spin structure of the proton and QCD dynamics at a high energy scale and is therefore complementary to existing semi-inclusive deep inelastic scattering experiments. Recent data from RHIC help to significantly constrain the gluon polarization contributing to the proton spin, and parity violating single spin asymmetries are observed for the first time in W production by both the PHENIX and STAR collaborations. In recent years, transverse spin phenomena have gained attention as they offer fundamental tests of our understanding of color forces, transversity, and orbital angular momentum. We present the latest results from the PHENIX and STAR experiments and will discuss the near and mid-term future prospects of the facility with an emphasis on the Drell-Yan mechanism. The talk will be summarized presenting the long term future of the facility the electron-ion collider.

Speaker: Elke Aschenauer (BNL)

Slides 1_ECA-RHICpp-Hadron2011.pptx

47 Recent developments in quarkonium production and open flavour production calculations

These are exciting times for quarkonium production. New theoretical advances are coinciting with the awaited measurement of new observables at the LHC. Progress has been made in testing different production mechanism for the heavy quarkonia. For instance, recently, a global data analysis of J/psi production within the framework of nonrelativistic QCD was performed at NLO accuracy, hinting at the universality of the so called long distance matrix elements. These developments will be reviewed here. As for open flavour production, there are two successful approaches on the market, interpolating between the fixed-flavour scheme (for low p_T) and the zero-mass parton model (for high p_T): The general-mass variable-flavour-number scheme (GM-VFNS) and the fixed-order NLL scheme (FONLL). Some recent results in the light of new LHC measurements will be presented here.

Speaker: Mathias Butenschön (Universität Hamburg)

Slides Butenschoen.pdf

48 Results on charmonium and charmonium-like production from the LHC

The recent results from the ALICE, ATLAS, CMS and LHCb experiments on charmonium and charmonium-like production in $pp$ collisions at the LHC, based on data collected in 2010, are presented. This talk will cover the following topics: - Strategy and results on the measurement of the differential cross-section of J/ψ production as a function of transverse momentum and rapidity; - The recent results on double J/ψ production, on exclusively produced J/ψ and ψ(2S); - Production of ψ(2S) and χc(1,2) at the LHC; - Production and mass measurement of X(3872). - Early results on Bc production.

Speaker: Yuanning Gao (Tsinghua University)

Slides Hadron2011-gao.pdf

1:00 PM Lunch Break

Heavy Hadrons: 3

Spectroscopy and decay of heavy hadrons

Convener: Prof. Christophorus Grab (ETH Zürich)

49 Heavy-quark masses and heavy-meson decay constants from Borel sum rules in QCD

We present the sum-rule extraction of the decay constants of the D, Ds, B, and Bs mesons from the two-point correlator of heavy-light pseudoscalar currents. We use the OPE of this correlator in terms of the running heavy-quark mass, for which the perturbative expansion exhibits a reasonable convergence. Our main emphasis is laid on the control over the uncertainties in the decay constants, related both to the input QCD parameters and to the limited accuracy of the method of sum-rules. The latter becomes possible due to the application of our procedure of extracting hadron observables that involves as novel feature dual thresholds depending on the Borel parameter. Our results for the decay constants contain the full analysis of both the statistical and systematic uncertainties.

Speaker: Prof. Dmitri Melikhov (HEPHY Vienna Austria & SINP Moscow Russia)

Slides Melikhov_Decay_constants_Hadron2011.pdf

50 First mass measurements at LHCb

Data collected in 2010 at the LHC is used by LHCb to perform the first preliminary mass measurements of b-hadron states fully reconstructed in modes decaying to a J/psi. The systematics on the momentum and mass scales, determined by the level of knowledge and understanding of the tracking system, are addressed. Precise mass measurements for B0, B+, Bs, Bc and Λb are reported. In several cases, competitive or statistically limited results are obtained, implying good prospects for future heavy-flavour spectroscopy measurements. In addition, first studies of excited B hadron states such as the Bs1 and Bs2* states in the B+K- system with the LHCb 2010 dataset will be presented.

Speaker: Roberta Cardinale (INFN - Genova)

Paper hadron2011.zip

Slides talk_hadron.v1.pdf

51 Spin-spin splittings and meson loops

The recent discovery of the bottomonia states h_b(1P) and h_b(2P) confirms the expectations of constituent quark models, already verified in the charmonia sector, that the spin-spin splitting of P-wave mesons is very small. The striking agreement is somewhat surprising because the non-relativistic quark model prediction, for which the splitting is identically zero, may be modified due to large mass shifts from coupling to open flavour meson pairs. Remarkably, in most models the spin-spin splitting remains small despite what are in many cases large mass shifts. This effect is shown to be a generic feature of models in which the coupling is driven by the creation of a spin one pair.

Speaker: Dr Timothy Burns (INFN Roma)

Slides munich.pdf

52 Measurement of heavy flavour production in pp and Pb-Pb collisions at the LHC with ALICE

Heavy-quarks are, due to their large mass, unique tools to probe the quark gluon plasma created in high-energy nuclear collisions. In proton-proton collisions, heavy-quark production comprises a fundamental challenge to theory and experiment. We report on recent results from the ALICE experiment on heavy flavour production in $pp$ and $Pb-Pb$ collisions at unprecedented high energies of $\sqrt{s} = 7$ TeV and $\sqrt{\mathrm{s}_{_{\mathrm{NN}}}} = 2.76$ TeV, respectively, as provided by the Large Hadron Collider. Open charmed hadrons are kinematically fully reconstructed in the hadronic decay channels $D^0\rightarrow K^-\pi^+$, $D^+\rightarrow K^-\pi^+ \pi^+$, and $D^{*+} \rightarrow D^0 (K^-\pi^+) + \pi^+$ and identified through their secondary decay-vertex topology. Inclusive charm and beauty production is measured by detecting electrons (muons) from semileptonic decays of open charmed and beauty hadrons in the central (forward) region. First results on nuclear modifications factors in $Pb-Pb$ collisions from hadronic and semi-leptonic decays are presented. Comparison to results from state-of-the-art QCD calculations is given.

Speaker: Dr Kai Schweda (University of Heidelberg)

Slides 4_hadron2011-schweda.ppt

Light Baryons: 3

Spectroscopy and structure (formfactors, parton distributions functions, spin) of light baryons

Convener: Prof. Eva-Maria Kabuss (Mainz university)

53 Process-dependent transverse momentum distributions from lattice QCD

Certain single-spin asymmetries in semi-inclusive DIS (SIDIS) and the Drell-Yan process (DY) can be explained by transverse momentum dependent parton distribution functions (TMDs) that are predicted to differ in sign for SIDIS and DY. On the lattice, we can use non-local operators with U-shaped Wilson lines to study these TMDs, in particular the Sivers- and the Boer-Mulders function. We discuss the method, its limitations and preliminary results from an exploratory calculation using lattices generated by the MILC and LHP collaborations.

Speaker: Dr Bernhard Musch (Jefferson Lab)

Paper proceedings_Musch_Hadron_2011.zip

Slides talk_Musch_20110614_Munich_Hadron2011.pdf

54 The light nuclei spin structure from the hadronic interactions at intermediate energies.

The experimental results on the deuteron analyzing powers for the dp-elastic scattering and the dd->3Hp(dd->3Hen) reaction at intermediate energies are reported. These data were obtained using polarized deuteron beams at Nuclotron (JINR, Russia) and RARF (RIKEN, Japan). The results on the analyzing powers Ay, Ayy and Axx in dp- elastic scattering obtained at Nuclotron at 880 MeV and 2000 MeV are compared with the predictions of several theoretical models. The importance of the rescattering effects and relativistic corrections is shown. The data on the tensor analysing powers for the dd->3Hp and dd->3Hen reactions obtained at RARF at 200 and 270 MeV demonstrate the sensitivity to the 3H, 3He and deuteron spin structures, especially, at the small scattering angles. The behavior of the analyzing powers at large scattering angles demonstrates the large discrepancy with the current theoretical calculations. The plans on the experimental studies of the polarization effects in dp- elastic scattering, dp-nonmesonic breackup, dd->3Hen(3Hp) and d3He->p4He reactions using internal and extracted beam at Nuclotron are presented.

Speaker: Dr Pavel Kurilkin (JINR. Dubna)

Paper pkurilkin_hadron2011.tar.gz

Slides hadron2011_pkurilkin.pdf

55 Cross section for quasi-real photo-production of charged hadrons with high transverse momenta in muon-deuteron scattering

The measurement of unpolarized high-$p_T$ hadron-production cross sections provides an important benchmark for the applicability of perturbative QCD (pQCD) calculations, especially at lower center-of- mass energies, where corrections beyond the next-to-leading order could become important. These calculations rely on the factorization of unpolarized and polarized cross sections into non-perturbative parton distribution functions, which parametrize the structure of the nucleon, hard scattering cross sections, calculable in pQCD, and non-perturbative fragmentation functions. In this contribution we shall present the first measurement of the unpolarized cross section for the quasi-real photo-production of charged hadrons with high transverse momenta from muon-deuteron scattering data at $/sqrt{s}=17.4$\,GeV at COMPASS. The dependence of the cross section on $p_T$ for forward and central rapidities is discussed. The presented cross section results are compared to recent NLO pQCD calculations.

Speaker: Mr Christian Hoeppner (TU Muenchen)

Slides 3_hoeppner_110614.pdf

56 Generalized Parton Distributions

to be filled

Speaker: Hervé Moutarde (Irfu, CEA-Saclay)

Paper source.zip

Slides 4_moutarde_hadron_2011.pdf

Low-Energy Processes: 1

Non-resonance physics

Convener: Prof. Achim Denig (Johannes Gutenberg University Mainz)

57 Chiral dynamics at KLOE, MAINZ, ELSA and other labs

A compact review of experimental tests of chiral dynamics involving the low lying pseudoscalars is presented with particular emphasis on results from KLOE and from the detectors operating at MAMI, at the ELSA facility, and at COSY. The status of the experimental knowledge on the dynamics of eta and eta’ decays is discussed and an outlook on future perspectives is given. Finally, the interplay between precise chiral calculation and accurate experimental measurements in leptonic K and pi decays is addressed.

Speaker: Prof. Fabio Ambrosino (Dipartimento di Scienze Fisiche Università degli Studi di Napoli "Federico II" e Sezione INFN Napoli)

Slides AmbrosinoHadron2011.pdf

58 πN scattering in relativistic baryon chiral perturbation theory revisited

We have analyzed pion-nucleon scattering using the manifestly relativistic covariant framework of Infrared Regularization up to {\cal O}(q^3) in the chiral expansion, where q is a generic small momentum. We describe the low-energy phase shifts with a similar quality as previously achieved with Heavy Baryon Chiral Perturbation Theory, \sqrt{s}\lesssim 1.14 GeV. New values are provided for the {\cal O}(q^2) and {\cal O}(q^3) low-energy constants, which are compared with previous determinations. This is also the case for the scattering lengths and volumes. Finally, we have unitarized the previous amplitudes and as a result the energy range where data are reproduced increases significantly.

Speaker: Mr Jose Manuel Alarcón (Universidad de Murcia)

59 Perturbative Treatment of Chiral Two Pion Exchange in Nucleon-Nucleon Scattering

In this talk I consider the perturbative renormalizability of chiral two-pion exchange within the effective field theory formulation of nuclear forces, provided that the one pion exchange potential has been fully iterated. This particular prescription implements the modified Weinberg counting proposal made by Nogga, Timmermans and van Kolck[1] up to next-to-next-to-leading order. It is shown that, by including the relevant counterterms, finite results can be obtained when the cut-off is removed, resulting in three counterterms for the singlet channel and six for the triplet. The previous result proves the viability of the Nogga, Timmermans and van Kolck counting, and confirms the related renormalization group analysis made by Birse [2] which predicted a similar number of counterterms for the central waves. Explicit calculations show that the present scheme yields a good description of nucleon-nucleon phase shifts up to a center-of-mass momentum of k ~ 200-300 MeV for the singlet and k ~ 300-400 MeV in the triplet [3]. The extension of the results to P- and D-waves is also discussed. References: [1] Phys.Rev.C72:054006,2005. [2] Phys.Rev.C74:014003,2006. [3] Phys.Rev.C83:024003,2011.

Speaker: Dr Manuel Pavon Valderrama (IFIC-UV)

Slides pavon-hadron11.pdf

60 Roy-Steiner equations for $\gamma\gamma\to\pi\pi$

Starting from hyperbolic dispersion relations, we present a system of Roy-Steiner equations for pion Compton scattering that respects analyticity and unitarity requirements, gauge invariance, as well as crossing symmetry, and thus all symmetries of the underlying quantum field theory. To suppress the dependence on the high-energy region, we also consider a once- and twice-subtracted version of the equations, where the subtraction constants are identified with dipole and quadrupole pion polarizabilities. We consider the resolution of the $\gamma\gamma\to\pi\pi$ partial waves by a Muskhelishvili-Omn\`es representation with finite matching point, and present the consequences for the two-photon coupling of the $\sigma$-resonance as well as its relation to pion polarizabilities.

Speaker: Mr Martin Hoferichter (Bonn University)

Slides hadron_2011_hoferichter.pdf

Quarkonia: 2

Production, spectroscopy, and decay of quarkonia

Convener: Prof. Nora Brambilla (Physik Department, TU Munich)

61 HEAVY QUARKONIA: Recent Results from CLEO

Recent results from CLEO in the spectroscopy of charmonium and bottomonium are presented. These include recent measurements of spin-singlet states in quarkonia, precision measurements of branching fractions for radiative and hadronic decays, and higher multipoles in radiative decays, among others.

Speaker: Prof. Kamal K. Seth (Nortwestern University)

Slides 1_hadron2011.pdf

62 Electric dipole transitions of heavy quarkonium

In this talk we will present the theoretical treatment of heavy quarkonia electric dipole transitions within an effective field theory formalism. Inside the effective field theory called potential nonrelativistic QCD (pNRQCD) we will account for the relativistic corrections to the decay rate in a systematic and model independent way. Former results from potential model calculations will be scrutinized and a phenomenological analysis in relation to the experimental data obtained by CLEO, BABAR & BELLE will be presented.

Speaker: Mr Piotr Pietrulewicz (Technische Universitaet Muenchen)

Paper Hadron_E1.tar.gz

Slides 2_Hadron-E1.pdf

63 Recent Results from the KEDR Detector

We present recent results from the KEDR detector operating at the e+e- collider VEPP-4M in Novosibirsk. They include a high-precision measurement of the J/psi and psi(2S) masses, a study of the psi(2S) and psi(3770) parameters, a determination of the branching fraction B(J/psi -> eta_c gamma), a test of lepton universality in J/psi decays, a measurement of the leptonic width for the psi(2S) and a search for narrow resonances in the c.m. energy range 1.85 GeV - 3.10 GeV.

Speaker: Dr Simon Eidelman (Budker Institute of Nuclear Physics)

Slides 3_ke11.pdf

64 APPLICATION OF HIGH QUALITY ANTIPROTON BEAM WITH MOMENTUM RANGING FROM 1 GeV/c TO 15 GeV/c TO STUDY CHARMONIUM AND EXOTICS

The study of strong interactions and hadronic matter in the process of antiproton-proton annihilation seems to be a challenge nowadays. The research of charmonium (the system consisting of charmed quark-antiquark pair cc\bar), charmed hybrids (the system consisting of charmed quark-antiquark pair strongly interacting with gluonic component cc\barg) spectra and their main characteristics: mass, width and branch ratios in experiments using antiproton beam with momentum ranging from 1 to 15 GeV/c at FAIR, are promising to understand the dynamics of quark interactions at small distances. Charmonium spectroscopy is a good testing tool for the theories of strong interactions: QCD in both perturbative and non-perturbative regimes, QCD inspired purely phenomenological potential models, non-relativistic QCD and LQCD. A possibility to study the charmonium spectrum and exotic states with the hidden charm in PANDA experiment at FAIR is considered. The reactions of antiprotons impinging on the proton or nuclear targets embedded in the High Energy Storage Ring will be studied in these experiments. The elaborate analysis of charmonium and charmed hybrid spectrum is carried out, and the attempts to interpret a great quantity of experimental data over DD\bar - pair are considered. But much more data on different decay modes are needed for a deeper analysis. These data can be derived directly from PANDA experiment with its high quality antiproton beam. The advantage of antiproton beam consists in intensive production of particle-antiparticle pairs which is observed in antiproton-proton annihilation. This fact allows one to carry out spectroscopic research with good statistics and high accuracy. Hence, there is a possibility of measuring the masses, widths and branch ratios of different charmonium and charmed hybrid states with high accuracy. Nowadays the scalar 1P1(hc), 1D2 and vector 3PJ(χ0,1,2), 3DJ - charmonium states and higher laying scalar 1S0(ηс) and vector 3S1(ψ) – charmonium states are poorly investigated. The domain over - threshold of 3.73 GeV/c2 is poorly studied. According to the contemporary quark models (LQCD, flux tube model), namely in this domain, the existence of charmed hybrids with exotic (JPC = 0+-, 1-+, 2+-) as with non-exotic (JPC=0-+, 1+-,2-+, 1++, 1--) quantum numbers is expected. During the last several years nearly twenty new states (particles) with the hidden charm were discovered by different experimental groups. Their interpretation is ambiguous nowadays. Most of these states were observed over the DD\bar - threshold in some definite channel (beside X(3872)-state). New particles were produced from B-meson decays and in electron-positron or two-photon collisions. The authors have proposed a combined approach based on the quarkonium potential model and relativistic top model for decay products to calculate the mass spectrum of radial excited states of charmonium and of charmed hybrids. One assumes that the decay potential has the finite radius beyond which the decaying charmonium or charmed hybrid are considered as collection of two relativistic tops in the same quantum state. The most interesting decay channels of charmonium (from theoretical and experimental viewpoints) pp\bar → cc\bar → ρπ, pp\bar → cc\bar → \Sigma0 \Sigma0\bar and decays into DD\bar - pair and decays with J/Ψ in the final state pp\bar → J/Ψ + X, were, in particular, considered. The masses of the particles participating in charmonium formation and decay are known with high precision. The mass spectra of the radial excited scalar and vector charmonium states and partially charmed hybrids were calculated in the framework of the combined approach up to the B-meson mass range. The results of the calculations have coincided with the existing experimental data within the experimental error. The existence of new states of charmonium and charmed hybrids over DD\bar - pair is expected. It was shown that some of the new states (recently discovered by experimental groups Belle, BaBar, CLEO, CDF) can be interpreted as higher laying scalar and vector radial excited states of charmonium. This treatment needs to be carefully verified in the future PANDA experiment. All charmonium states can be directly formed in pp\bar - annihilations through the coherent annihilation of three quarks in the proton with three antiquarks in the antiproton. With this method their masses and widths can be measured with excellent accuracy, determined by the precise knowledge of the initial pp\bar - state and not limited by the resolution of the detector. It becomes possible to extract the information about the excited states of charmonium in these experiments which can be extremely useful to study the strong coupling nature. Using the integral approach, the widths of the expected states of charmonium were calculated. It has been demonstrated that widths of the predicted charmonium states are also narrow and don’t have anomalous large values.

Speaker: Dr Mikhail Barabanov (Joint Institute for Nuclear Research)

Paper hadron2011_barabanov.pdf hadron2011_barabanov.zip

Slides HADRON2011_BARABANOV.pdf

4:00 PM Coffee Break

Hadrons in Hot and Cold Medium: 2

Heavy ions, mesons in nuclei, and hypernuclei

Convener: Prof. Tullio Bressani (INFN-Sezione di Torino)

65 Photoproduction of η' Mesons from Nuclei

Mariana Nanova University of Giessen, Germany for the CBELSA/TAPS Collaboration Studies of in-medium properties of the η' meson will be presented. The photoproduction of η' mesons off 12C, 40Ca, 93Nb and 208Pb nuclei has been measured. The experiment was performed at the ELSA accelerator in Bonn with the combined setup of the Crystal Barrel and TAPS detectors. Recent results on the in-medium width of the η' meson, derived from the transparency ratio measurements, will be presented and compared with results for the ω and η meson and with theoretical calculations. The momentum dependence of the transparency ratio and the absorption of the η' meson in nuclear matter as a function of its kinetic energy will be discussed. ⋆Funded by DFG(SFB/TR-16)

Speaker: Dr Mariana Nanova (II. Physikalisches Institut, Universität Giessen)

Slides nanova_hadron2011_m.pdf

66 K* mesons in matter

The properties of the K*- meson in dense matter are studied using a unitary approach in coupled channels within the framework of the local hidden gauge formalism. We obtain the K*- spectral function in the nuclear medium and we found that the K*- develops an in-medium width up to five times bigger than in free space. We also estimate the transparency ratio of the \gamma A -> K+ K*- A' reaction, which we propose as a feasible experimental scenario to detect in-medium modifications of the K*- meson.

Speaker: Mrs Raquel Molina (IFIC)

Paper proc_kstmedio.tar.gz

Slides 2_presentkstar2.pdf

67 Measurement of the in-medium $\phi$-meson width in proton-nucleus collisions

The production of $\phi$-mesons in collisions of 2.83 GeV protons with C, Cu, Ag and Au targets has been measured with the ANKE magnetic spectrometer at the Cooler Synchrotron COSY. The $\phi$ was detected at small angles via its $K^+K^-$ decay branch. The measured target mass dependence of the production cross section can be related to the in-medium $\phi$ width. Comparisons with available model calculations suggest a significant broadening of this width relative to the vacuum value of 4.3~MeV/$c^2$. Since this was a high statistics experiment, with 7000-10000 $\phi$ per target, we were able to study the momentum dependence of the in-medium $\phi$ width and results will be presented in the range $0.6 < p_\phi < 1.6~$GeV/$c$.

Speaker: Mr Andrey Polyanskiy (IKP, FZ Jülich)

Paper hadron2011_apolyanskiy.zip

Slides APolyanskiyHadron2011.pdf

68 Measuring the J/Psi-Nucleon dissociation cross section with PANDA

With the PANDA detector at the HESR at FAIR it will be possible to study the production of charmed hadrons on nuclear targets. One reactions of particular interest is the formation of J/Psi mesons when a nuclear target is bombarded with antiprotons. If the momentum of the incident antiprotons is properly selected, then they can annihilate with protons in the nucleus of a target atom and form a J/Psi meson. The formed J/Psis have relatively small momenta with respect to the nucleus and therefore act as a probe of the nuclear medium. In this talk I will report on a study of the possibility to measure with PANDA the probability for the J/Psi mesons to be dissociated before they escape from the nucleus. This nuclear dissociation cross-section is relevant for the interpretation of the J/Psi suppression observed in high energy heavy ion reactions, a possible signature of the existence of a quark-gluon plasma.

Speaker: Dr Paul Buehler (Stefan Meyer Institute, VIenna)

Slides 4_pbuehler_hadron2011.pdf

69 Precision Spectroscopy of Pionic Atom at RIKEN-RIBF

Precision spectroscopy of pionic atoms provide unique information on the isovector πN interaction which connected to reduction of the chiral symmetry breaking at the normal nuclear density. Recent experiments at GSI on Sn isotopes yielded the first quantitative estimation of its reduction to be about 33% compared to that in the vacuum [1]. We are working on a new experimental project, namely the pionic atom factory project at the RI beam factory in RIKEN [2]. The objective of this project covers spectroscopy of wide range of pionic atoms with stable nuclei with the world highest resolution. In October 2010, we performed a pilot experiment of this project and measured the energy spectrum of the 122Sn(d,3He) reaction. In my talk, I will report preliminary experimental results of this experiment. [1] K. Suzuki et al, Phys. Rev. Lett. 92, 072302 (2004). [2] K. Itahashi et al, RIBF proposal 27 and 54.

Speaker: Mr Satoshi Itoh (University of Tokyo)

Paper hadron2011_itoh.zip

Slides 5_itoh_hadron2011.pdf

Light Baryons: 4

Spectroscopy and structure (formfactors, parton distributions functions, spin) of light baryons

Convener: Prof. Mauro Anselmino (Torini University &amp; INFN)

70 Spin physics at COMPASS

The COMPASS experiment is a fixed target experiment at the CERN SPS using muon and hadron beams for the investigation of the spin structure of the nucleon and hadron spectroscopy. The main objective of the muon physics programme is the study of the nucleon spin. COMPASS has accumulated data during 6 years scattering polarised muons off a longitudinally or a transversely polarised deuteron ($^6$LiD) or proton (NH$_3$) target. Results for the gluon polarisation are obtained from double spin cross section asymmetries using two different channels, open charm production and high transverse momentum hadron pairs, both proceeding through the photon-gluon fusion process. Also, the longitudinal spin structure functions of the proton and the deuteron were measured in parallel as well as the helicities for the three lightest quark flavours. On the transversity side, results were obtained with proton and deuteron targetsfor the Collins and Sivers asymmetries for charged hadrons as well as for identified kaons and pions. The Collins asymmetry is sensitive to the transverse spin structure, while the Sivers asymmetry reflects correlations between the quark transverse momentum and the nucleon spin. Recently, a new proposal for the COMPASS II experiment was accepted by the CERN SPS which includes two new topics: Exclusive reactions like DVCS and DVMP using the muon beam and a hydrogen target to study generalized parton distributions and Drell-Yan measurements using a pion beam and a polarised NH_3 targetto study transverse momentum dependent distributions.

Speaker: Prof. Eva-Maria Kabuss (Mainz university)

Slides 1_Kabuss.pdf

71 QUARK FRAGMENTATION FUNCTIONS FROM SIDIS HADRON MULTIPLICITIES IN COMPASS

Fragmentation functions (FF) describe the process of fragmentation of quarks into hadrons. They are needed for the determination of polarized and unpolarized quark distribution functions from semi-inclusive deep inelastic scattering (SIDIS) data. While the pion FFs are reasonably well determined, kaon FFs are poorly known and provide the largest source of uncertainty for the extraction of the polarized strange quark distribution function. FFs are non-perturbative quantities which were first determined from high energy e+e- data. The COMPASS collaboration has recently measured pion and kaon multiplicities in SIDIS. These data can be used as input to global QCD analyses to determine FFs. The current status of the leading order extraction of the fragmentation functions from SIDS data collected by the COMPASS experiment will be presented.

Speaker: Ms Nour Makke (CEA/Saclay)

Slides 2_Makke_Had11.pdf

72 The K⁻ d -> Lambda(1405) n reaction with the DAFNE set up and the two Lambda(1405) states

The K^- induced production of Lambda(1405) is investigated in K^- d to pi Sigma n reaction based on coupled-channels chiral dynamics, in order to discuss the mass of the Lambda(1405) and the prediction of two Lambda(1405) states made by the chiral unitary theory. We find that the K^-d to Lambda(1405)n process favors the production of Lambda(1405) initiated by the KbarN channel, which favors the Lambda(1405) at higher energy. The present approach indicates that the Lambda(1405) resonance position is 1420 MeV rather than 1405 MeV in the pi Sigma invariant mass spectra of K- d to pi Sigma n reactions. This is consistent with an observed spectrum of the K^- d to pi^+ Sigma^- n with 686-844 MeV/c incident K^- by bubble chamber experiments done in the 70's. Our model also reproduces the measured Lambda(1405) production cross section [1]. After that, we have evaluated the cross sections for the K^- induced production of Lambda(1405) in the K^- d to pi Sigma n reaction, having in mind the conditions of the DAFNE facility at Frascati where kaons are obtained from the decay of slow moving phi mesons. We also find that the K^- d to Lambda(1405) n process favors the production of Lambda(1405) initiated by the K^- p channel, which gives largest weight to the higher mass Lambda(1405) appearing at 1420 MeV in chiral theories. We find that the fastest kaons from the decay of the phi are well suited to see this resonance, particularly if one selects forward going neutrons in the center of mass, which reduce the contribution of single scattering and make the double scattering dominate where the signal of the resonance appears clearer [2]. [1] D. Jido, E. Oset and T. Sekihara, Eur.Phys.J. A42 (2009) 257-268 [2] D. Jido, E. Oset and T. Sekihara, Eur.Phys.J. A47 (2011) 42

Speaker: Eulogio Oset (IFIC , University of Valencia)

Slides 3_Osetdafne.pdf

73 Mesons and baryons in holographic soft-wall model

Mesons and baryons are considered in a soft-wall holographic approach [1,2] based on the correspondence of string theory in AdS space and conformal field theory in physical space-time [3]. Our approach is also based on ideas of the light-front holography approach developed by Brodsky and de Teramond [4]. The model generates Regge trajectories linear in n and J(L) for the hadronic mass spectrum. Results obtained for heavy-light meson masses and decay constants are consistent with predictions of HQET. The role of the dilaton field in a soft-wall holographic approach for mesons and baryons is discussed. In the baryon sector we present application to the nucleon electromagnetic form factors and the generalized parton distributions [2]. [1] A. Vega, I. Schmidt, T. Branz, T. Gutsche, V. E. Lyubovitskij, Phys. Rev. D80, 055014 (2009); T. Branz, T. Gutsche, V. E. Lyubovitskij, I. Schmidt, A. Vega, Phys. Rev. D82, 074022 (2010); T. Gutsche, V. E. Lyubovitskij, I. Schmidt, A. Vega, in preparation. [2] A. Vega, I. Schmidt, T. Gutsche, V. E. Lyubovitskij, Phys. Rev. D83, 036001 (2011). [3] J. M. Maldacena, Adv. Theor. Math. Phys. 2, 231 (1998); S. S. Gubser, I. R. Klebanov, A. M. Polyakov, Phys. Lett. B428, 105 (1998); E. Witten, Adv. Theor. Math. Phys. 2, 253 (1998). [4] S. J. Brodsky, G. F. de Teramond, Phys. Lett. B582, 211 (2004); Phys. Rev. D77, 056007 (2008); Phys. Rev. Lett. 102, 081601 (2009).

Speaker: Dr Valery Lyubovitskij (Institute of Theoretical Physics, Tuebingen University)

Slides Lyubovitskij.pdf

74 A plausible explanation of the Delta_{5/2^{+}}(2000) puzzle

From a Faddeev calculation for the pion-(Delta rho)(N(1675)) system, performed with the Fixed Center Approximation within a Chiral Unitary framework, we show the plausible existence of three dynamically generated I (JP) = 3/2 (5/2+) baryon states below 2.3 GeV whereas only two resonances, Delta(5/2+) (1905) (∗∗∗∗) and Delta(5/2+) (2000) (∗∗), are cataloged in the Particle Data Book Review[1]. However, a careful look at Delta(2000)(5/2+) (∗∗), shows that its nominal mass is in fact estimated from the masses (1724±61), (1752±32) and (2200±125) respectively extracted from three independent analyses of different character[2,3,4]. Moreover a recent new data analysis[5] has reported a Delta(5/2+)with a pole position at 1738 MeV. Our results give quantitative theoretical support to the existence of two distinctive resonances, Delta(5/2+)(∼1740) and Delta(5/2+)(∼2200). We propose that these two resonances should be cataloged instead of Delta(5/2+)(2000). This proposal gets further support from the possible assignment of the other calculated baryon states in the I = 1/2, 3/2 and spin-parity JP =1/2+, 3/2+ sectors to known baryonic resonances. In particular the poorly established Delta(1/2+) (1750)(∗) may be naturally interpreted as a pion-N(1/2-)(1650) bound state. [1], K. Nakamura et al., J. Phys. G 37, 075021 (2010). [2], D.M. Manley and E.M. Saleski, Phys. Rev. D 45, 4002 (1992). [3],T. P. Vrana, S. A. Dytman and T.-S. H. Lee, Phys. Rep. 328, 181 (2000). [4],R.E. Cutkosky, C.P. Forsyth, J.B. Babcock, R.L. Kelly, and R.E. Hendrick, Proceedings of the IV International Conference on Baryon Resonances (Baryon 1980), edited by N. Isgur, Toronto 1980. [5],N. Suzuki et al. (EBAC), Phys. Rev. Lett. 104, 042302 (2010).

Speaker: Prof. Pedro Gonzalez (University of Valencia)

Slides Gonzalez_HADRON11.ppt

Light Mesons: 3

Spectroscopy and decay of light mesons

Convener: Dr Dennis Weygand (Jefferson Laboratory)

75 Pion form factor in a broad range of momentum transfers from local-duality QCD sum rule

We calculate the pion form factor making use of a local-duality (LD) version of QCD sum rules. To probe the accuracy of the obtained predictions we consider in parallel to QCD a potential model with an interaction consisting of Coulomb and confining parts. In this case, the exact form factor may be obtained from the solution of the Schrödinger equation and confronted with the result from the quantum-mechanical LD sum rule. We employ parameters of the potential model appropriate for hadron physics and show that, independently of the details of the confining interaction, the maximal deviation of the LD form factor from the exact form factor is observed in the region Q²=4-8 GeV². At higher Q, the accuracy of the LD sum rule increases rather fast with Q. In QCD, no disagreement between the LD sum rule for the pion form factor and experimental data at Q²=1-6 GeV² has been observed until now. We argue that this feature leads to important consequences for the pion form factor at larger momentum transfers, up to the asymptotically large values.

Speaker: Prof. Dmitri Melikhov (HEPHY Vienna Austria & SINP Moscow Russia)

Slides Melikhov_talk_Fpi.pdf

76 Precision calculation of the pion electromagnetic form factor from lattice QCD

We present a lattice calculation of the vector form factor of the pion for two flavours of non-perturbatively O(a) improved Wilson fermions. For the measurements we utilise the CLS ensembles which include various lattice spacings and pion masses down to roughly 250 MeV. To obtain a fine momentum resolution near zero momentum transfer (q^2) twisted boundary conditions are employed using several properly tuned twist angles. In order to keep statistical fluctuations small we use stochastic wall sources for the computation of the propagators. Due to the fine resolution around q^2=0 we are able to determine the slope of the form factor and, in turn, extract the charge radius of the pion without any model dependence. Thereby, systematic effects for the latter are significantly reduced. The results for the form factor and the charge radius are then compared to chiral perturbation theory and other models which are then used to extrapolate the results to the physical point.

Speaker: Mr Bastian Brandt (Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, Mainz)

Paper hadron2011_brandt.tar.gz

Slides Vortrag.pdf

77 Determination of the eta transition form-factor from the eta --> e+ e- gamma decay

Volker Metag University of Giessen, Germany for the A2 collaboration The Dalitz decay η → γe+e− has been investigated in photo-nuclear reactions with the Crystal Ball/TAPS detector system at the electron accelerator MAMI-C. The Dalitz decay events were identified in an exclusive analysis exploiting the full kinematic information. Statistics improved by an order of magnitude compared to the most recent measurement in the e+e− channel allowed to determine the slope bη of the electromagnetic transition form factor F (q2) = (1 − q2/Λ2)−1 to bη = Λ−2 = (1.89 ± 0.35(stat) ± 0.1(syst)) GeV−2. This value is in good agreement with a recent measurement of the η Dalitz decay in the μ+μ− channel and with recent form-factor calculations. An improved branching ratio BR(η → γe+e−) = (6.21 ± 0.50) · 10−3 has been determined. Funded by DFG(SFB/TR-16)

Speaker: Prof. Volker Metag Metag (II. Physikalisches Institut)

Slides Metag_HADRON-11_eta-FF_s_anim.pdf

78 Hadron Physics at KLOE and KLOE-2

The KLOE experiment has collected 2.5 fb-1 at the peak of the phi resonance at the e+e- collider DAPHNE in Frascati. The whole data set includes 100 million eta's produced through the radiative decay phi --> eta gamma and tagged by means of the monochromatic recoil photon. Measurements of eta decay channels, such as pi+ pi- gamma, are in progress. We have also measured the branching ratio of the eta --> e+ e- e+ e- decay channel, never observed before, with a sample of about 360 events. Pseudoscalar production at the phi-factory associated to internal conversion of the photon into a lepton pair allows the measurement of the form factor F(q1^2=M(phi)^2,q2^2>0) of pseudoscalar mesons in the kinematical region of interest for the VMD model. The only existing data on phi --> eta e+ e- are based on 213 events. At KLOE, a preliminary study of this decay has been performed on 739 pb-1 using the eta-->pi+pi-pi0 final state. Simple analysis cuts provide about 7000 signal events with very small residual background contamination. From a sample of 240 pb-1 taken off the phi resonance, a preliminary analysis of the e+ e- --> e+ e- eta process, without tagging e+e- in the final state is presented. Using two different decay channels, eta --> pi+ pi- pi0 and eta --> pi0 pi0 pi0, the cross section of the process e+ e- --> e+ e- eta is extracted. The same data set has been used to search for the f0(600) that can be produced in gamma-gamma interactions and observed in the reaction e+ e- --> e+ e- pi0 pi0. The preliminary pi0pi0 mass spectrum show an excess of events with respect to the expected background in the f0(600) mass region. A new beam crossing scheme allowing for a reduced beam size and increased luminosity is operating at DAPHNE. The KLOE-2 detector is successfully rolled in this new interaction region and is ready to acquire collision data. At the moment, the detector is being upgraded with small angle tagging devices, to detect both high and low e+e- energy in e+ e- --> e+ e- X events. The inner tracker and small angle calorimeters are scheduled to be installed in a subsequent step, providing wider acceptance for both charged particles and photons. The main goal of KLOE-2 is to collect an integrated luminosity of about 20 fb^-1 in 2-3 years in order to refine and extend the KLOE physics programme.

Speaker: Dr camilla di donato (INFN Sez. Napoli)

Paper http://arxiv.org/abs/1109.3968

Slides KLOE-KLOE2_Hadron11.pptx

79 Analysis of diffractive dissociation of exclusive $K^{-} \pi^{+} \pi^{-}$ events in the high energetic hadron beam of the COMPASS-experiment

In order to study the light mesons spectrum the COMPASS experiment at CERN took data with a 190 GeV/c hadron beam hitting a liquid hydrogen target in the years 2008 and 2009. The negative hadron beam contains mainly pions and a small fraction of about 2.5\% of kaons. Kaons are identified using CEDAR PID detectors in the beamline. One of the channels of interest are diffractively produced resonance decaying into the $K^-$ $\pi^+$ $\pi^-$ final state. I will discuss the data selection and quality studies for this channel. The invariant mass spectra show already the well known resonances as the $K_1(1270)$ $K_1(1400)$ and the $K_2(1770)$. To disentangle all contributing resonances techniques of partial wave analysis are applied. A short review on this studies will be presented. Supported by BMBF under the contract 06MZ224

Speaker: Mr Prometeusz Jasinski (INP Mainz)

Paper jasinski-proceedings.tar.gz

Slides jasinski_hadron_2011.pdf

Quarkonia: 3

Production, spectroscopy, and decay of quarkonia

Convener: Dr Simon Eidelman (Budker Institute of Nuclear Physics)

80 Recent BABAR Studies of Bottomonium States

We present a study of the radiative transitions from decays of the Y(2S) and Y(3S) resonances using photons that have converted into an e+e- pair, obtaining precise measurements of the branching fractions for chi_b1,2(1, 2P) --> gamma Y(1S) and chi_b1,2(2P) -->gamma Y(2S) transitions and search for radiative decay to the eta_b(1S) and eta_b(2S) states. We present a search for the spin-singlet partner of the chibJ(1P) triplet, the hb(1P) state of bottomonium in the transitions Y(3S)-->pi0 hb and Y(3S)-->pi+pi-hb using a data sample of 122 million Y(3S) events.

Speaker: Claudia Patrignani (University and INFN Genova)

Slides patrignani_HADRON2011_babar.pdf

81 Bottomonium results at Belle

Originally designed for CP violation studies in the B meson system, the B-Factories recently showed an exciting capability for improving our experimental knowledge in the field of hadron spectroscopy. We review results on bottomonium spectroscopy by the Belle experiment at the KEK-B e+e- collider and present exciting new results from the unique large data set taken at the Y(5S) resonance.

Speaker: Dr Alexander Kuzmin (BINP)

Paper kuzm.trz

Slides 2_hadr_kuzmin.pdf

82 Mass dependence of the heavy quark potential and its effects on quarkonium states

The heavy quark-antiquark potential is accessible in perturbative QCD and in lattice simulations. The perturbative short-distance part of the potential is contructed via a restricted Fourier transform, covering the momentum region where perturbative QCD is applicable. We show that for the leading order static term as well as for the mass dependent corrections, the perturbative part can be matched at intermediate distances with results from lattice QCD. From these matched potentials, quarkonium spectra with a single free parameter (the heavy quark mass) are derived and compared with empirical spectra. Furthermore, charm and bottom quark masses are deduced.

Speaker: Alexander Laschka (TU München)

Slides laschka.hadron2011.pdf

83 Quarkonia measurements in dimuon final states at LHCb

LHCb is one of the four LHC experiments which started data-taking in 2010 at a centre-of-mass energy of 7 TeV. The detector is a forward spectrometer dedicated to the study of B production and decay. Efficient tracking and muon identification allow precision measurement of quarkonia states to be performed. We present studies of the production of resonances in the dimuon sample collected in the first year of data taking corresponding to about 34 pb–1. We will discuss the double differential cross section measurements of J/ψ, double J/ψ, ψ(2S), Υ, and their impact on the understanding |of quarkonia production. The results will be discussed in the context of the predictions of several theoretical models. Prospects for the measurement of quarkonia polarization will also be discussed.

Speaker: Giovanni Sabatino (INFN - Rome 2)

Paper template.tar.gz

Slides Sabatino_hadron2011.pdf

84 Quarkonium production in pp collisions at 7 TeV with the CMS experiment

This talk presents the quarkonium differential cross sections, as a function of transverse momentum and in several rapidity ranges, measured by CMS in pp collisions at 7 TeV. In particular, results will be presented for the J/psi and psi(2S) states as well as for the Υ(1S), Υ(2S) and Υ(3S). We will also provide first results regarding the production of the chi_c states and of the X(3872) exotic state. The B to J/psi and B to psi(2S) fractions will also be discussed. Wherever suitable, our measurements will be compared to other measurements, as well as to theory calculations.

Speaker: Bora Akgun (Carnegie Mellon University)

Slides Hadron11_QuarkoniaWithCMS.pdf

6:10 PM Conference group photo

Poster Session

85 A bound state of $N \rho \rho $ in the fixed center approximation of Faddeev equation

The $N\rho\rho$ three-body system has been studied within the framework of fixed center approximation of Fadeev equation, and the scattering amplitudes show a peak around 2200MeV. It manifests the interaction among $N\rho\rho$ system is strong enough to generate a bound state with a mass about 2200MeV. Moreover, another peak of the amplitudes appears at the higher energy range, which might correspond to a resonance state of the $N\rho\rho$ system.

Speaker: Dr Bao-Xi SUN (IFIC, Universidad de Valencia)

Paper sunbx.zip

86 About the contact term in the omega->3 pion process from the Vector Dominance point of view.

The omega->3 pion process is known to be dominated by the omega-rho-pi transition, followed by the decay of the rho meson into two pions. However, this does not deny the possibility of the need of a contact term, as can be seen in other works, to reproduce the experimental value of the decay width of the omega meson into three pions. In this work, we revisit the omega->3 pion process under the Vector Meson Dominance scheme (VMD). We obtain its width by considering only the rho channel, fixing the omega-rho-pi coupling from radiative decays. We restate the possible need of the contact term to account for the deviations from the experimental value. Using the VMD ideas, we mimic the contact term by a higher resonance (namely the rho′(1450) meson) which, in contrast with previous works, possess a structure at high energies, while at low energies behaves as a constant. We have found that under such considerations the numerical value of the contact term is similar to the other estimates and therefore satisfy the corresponding requirements. We also determine at which extent it is possible to ignore such contact term in the VMD scheme while being consistent with other observables. In order to do so, we have calculated the cross section for the e+ e− ->omega->3 pi process. By comparing with the experimental data when excluding/including the contact term and varying the omega-rho-pi coupling within the corresponding error bars, we have found that a value of 12.39±1.5 GeV^-1 for this coupling is in agreement with both the e+ e− ->omega->3 pi cross section, the omega->3 pi decay width and the related radiative decays by VMD. Due to the large uncertainties involved it is not possible to be conclusive about the contact term.

Speaker: David Garcia (Instituto de Física, UNAM)

Paper David_Garcia__Gudiño_hadron_2011_proceedings.zip

87 Charmonium spectra at finite temperature from a Bayesian analysis of QCD sum rules

Charmonium spectral functions at finite temperature are investigated, using QCD sum rules in combination with the maximum entropy method. This approach makes it possible to directly obtain the spectral function from the sum rules, without having to introduce any specific assumption about its functional form. QCD sum rules incorporate finite temperature effects by the change of the various gluonic condensates that appear in the operator product expansion. These changes depend on the energy density and pressure at finite temperature, which we extract from lattice QCD. We find that while J/psi and eta_c manifest themselves as clear peaks in the spectral function below the deconfinement temperature T_c, they dissolve into the continuum already at temperatures between 1.0 T_c and 1.1 T_c.

Speaker: Mr Philipp Gubler (Tokyo Institute of Technology)

Paper forsubmission.zip

88 Chiral and isospin symmetry breaking: order parameters and susceptibilities

We analyze the order parameters of chiral and $SU_V(N_f)$ symmetry breaking, as well as their isoscalar and isovector susceptibilities. For that purpose, we include $m_u\neq m_d$ and electromagnetic corrections in a consistent leading order Chiral Perturbation Theory framework for $N_f=2,3$, providing model-independent predictions. At zero temperature and assuming the QCD vacuum to have a ferromagnetic-like behaviour, we show that the increasing of the quark condensate under explicit chiral symmetry breaking induced by electromagnetic corrections leads to constraints for the electromagnetic low-energy constants (LEC) which are checked with different LEC determinations in the literature. We also analyze matching conditions between $SU(2)$ and $SU(3)$ as well as corrections to the sum rule relating quark condensate ratios \cite{Nicola:2010xt}. At finite temperature, the isospin breaking order parameter $\langle\bar uu-\bardd\rangle$ grows with $T$ for $SU(3)$, $T_c$ being almost unaffected. We obtain a sum rule relating EM corrections to the quark condensate with isoscalar susceptibility differences $\chi(T)-\chi(0)$, which can be also useful for estimating errors in staggered lattice analysis. Keeping $m_u\neq m_d$ allows us to separate neatly the quark connected and disconnected susceptibilities, whose mass and temperature behaviour we analyze in detail. Near chiral restoration, the disconnected part grows linearly, diverging in the infrared chiral limit as $T/M_\pi$, while the connected part has an infrared regular behaviour $T^2/M_\eta^2$ coming from $\pi^0-\eta$ mixing. We explore some consequences in connection with lattice data and their scaling properties, for which our present analysis for physical masses, i.e. beyond the chiral limit, provides a useful description for the hadron gas at low and moderate temperatures \cite{Nicola:2011gq}. \begin{thebibliography}{99} \bibitem{Nicola:2010xt} A.~G.~Nicola and R.~T.~Andres, %``Isospin-Breaking quark condensates in Chiral Perturbation Theory,'' arXiv:1009.2170 [hep-ph]. %%CITATION = ARXIV:1009.2170;%% \bibitem{Nicola:2011gq} A.~G.~Nicola and R.~T.~Andres, %``Isospin Breaking and chiral symmetry restoration,'' Phys.\ Rev.\ D {\bf 83}, 076005 (2011). arXiv:1101.5362 [hep-ph]. %%CITATION = ARXIV:1101.5362;%% \end{thebibliography}

Speaker: Mr Ricardo Torres-Andres (Universidad Complutense de Madrid)

89 Dalitz Decay of Pseudoscalar Mesons from Photoproduction on Hydrogen Target with CLAS

Experimental results on the Dalitz decay of P(π0, η, η’)->e+ e- γ pseudoscalar mesons produced in the photoproduction reaction γ + p -> P(π0, η,η’) + p on a Hydrogen target with CLAS are presented for the first time. The total statistics collected for η Dalitz decay exceeds the world’s published statistics by an order of magnitude, while the Dalitz decay of η’->e+ e- γ is observed and measured for the first time. The data obtained will allow for an update on already measured branching ratios and provide branching ratio of η’ in this channel. Current status of analysis and future prospects are discussed.

Speaker: Mr Michael Kunkel (Old Dominion University)

90 Diffractive pion dissociation into $(K_sK^{\pm}\pi^{\mp}\pi^{-})$ final states

The COMPASS experiment at CERN SPS is dedicated to the study of hadron structure and spectroscopy. One goal of the physics programme using hadron beams is the search for new states, in particular the search for $J^{PC}$ spin-exotic states and glueballs. COMPASS has started to contribute to the puzzle of the existence of spin-exotic mesons by the published 2004 pilot run data, showing a significant production strength for an exotic $J^{PC}=1^{-+}$ state at 1.66\,GeV/${\rm c^2}$~[1], the newly taken 2008/09 data will further clarify the situation. Apart of the spin-exotic $\pi_1(1600)$ resonance observed in various decay channels and experiments, also a spin-exotic $\pi_1(2000)$ was reported in the past in the $f_1(1285)\pi$ decay channel by the E852 experiment at BNL [2], however, this state still lacks any confirmation. We present a first event selection of the diffractively produced $(K\bar{K}\pi\pi)^{-}$ system showing clean $f_1(1285)$ and $f_1(1420)$ resonances at competing statistics with BNL, and extending the spectrum beyond 2\,GeV/${\rm c^{2}}$. A partial-wave analysis started on $f_1(1285)\pi$ and $f_1(1420)\pi$ decay channels will further complete the search for spin-exotics in the 2008/09 COMPASS data, the $f_1(1420)\pi$ system was never studied before. \\\\ $\lbrack 1 \rbrack$ M.~Alekseev {\it et al.}, COMPASS collaboration, {\it Phys. Rev. Lett}, {\bf 104} (2010) {241803}.\\ $\lbrack 2 \rbrack$ J.~Kuhn {\it et al.}, {\it Phys. Lett. B} {\bf 595} (2004) {109}.

Speakers: Dr Frank Nerling (University of Freiburg), Johannes Bernhard (Institut f. Kernphysik, JGU Mainz)

Poster bernhard_nerling_hadron2011.pdf

91 Discharge of metastable nuclei during negative muon capture: Energy approach

A negative muon captured by a metastable nucleus may accelerate the discharge of the latter by many orders of magnitude [1,2]. For a certain relation between the energy range of the nuclear and muonic levels a discharge may be followed by muon ejection and muon- participates in discharge of other nuclei. We present relativistic energy approach to a discharge of a nucleus with emission of gamma quantum and further muon conversion, which initiates this discharge [3]. Besides, the external graser effect on cited processes is studied. The decay probability is linked with imaginary part of the "nucleus core+ external nucleon+muon" system energy. One should consider 3 channels: 1). radiative purely nuclear 2j-poled transition (probability P1); 2). Non-radiative decay, when a proton transits into the ground state and muon leaves a nucleus with energy E=E(p-N1J1)-E(i), where E(p-N1J1) is an energy of nuclear transition, E(i) is the bond energy of muon in 1s state (P2); 3). A transition of proton to the ground state with muon excitation and emission of gamma quantum with energy E(p-N1J1)-E(nl) (P3). Under condition E(p-N1J1)>E(i) a probability definition reduces to QED calculation of probability of autoionization decay of 2-particle system. As example, data for Sc, Tl nuclei are listed. The Dirac-Wood-Saxon model is used. As illustration for Sc nucleus below we present values for the probabilities of the muon-Sc decay for different transitions: P2(p1/2-p3/2)=3,931015, P2(p1/2-f7/2)= 3.15*10(12), P2(p3/2-f7/2)=8.83*10(14). Here the nucleus must transit the momentum no less than 2,4 and 2 according to the momentum and parity rules. If a muonic atom is in the initial state p1/2, than the cascade discharge occur with ejection of muon on first stage and secondly the gamma quantum emission. To consider a case when the second channel is closed and the third one is opened, suppose: E(p1/2)-E(p3/2)=0.92 MeV. Energy of nuclear transition is not sufficient to transit muon into continuum state and it may excite to 2p state. Then, there is the proton transition p1/2-p3/2 with virtual muon excitation to states of nd series and gamma quantum emission ħw=Ep(p1/2)+Em(1s)- Ep(p3/2)-Em(2p). The dipole transition 2p-1s occurs with P3=1.9*10(13) s-1 (more than P(p1/2-p3/2), P(p1/2-f7/2 ) transitions without radiation. References: 1. V.I.Gol'dansky, V.S.Letokhov, JETP.1974.V.67.P.513; L.N.Ivanov, V.S.Letokhov, JETP. 1976. V.70.P.19; A.V.Glushkov, L.N.Ivanov, Phys.Lett.A.1992.V.170.P.33. 2. A.Glushkov, Low Energy Antiproton Physics (AIP).2005.V.796.P.206. 3. A.V.Glushkov et al, Frontiers in Quantum Systems in Phys. and Chem. Series: Progress in Theor.Phys.(Berlin, Springer). 2006.V.15. P.301; 2011.V.21.P.131.

Speaker: Prof. Alexander Glushkov (Odessa University and Troitsl ISAN Russian Acad. Sci.)

92 Dynamical generation of pseudoscalar resonances

The interactions between the f_0(980) and a_0(980) scalar resonances and the lightest pseudoscalar mesons are studied. The interacting kernels are obtained without including any ad hoc free parameter, thanks to previous results on the nature of the lightest scalar resonances as dynamically generated from the rescattering of S-wave two-meson scattering. The amplitudes are then unitarized, and the final S-wave amplitudes are obtained. The resulting interactions are found to be very rich and generate a large amount of pseudoscalar resonances that we associate with the K(1460), \pi(1300), \pi(1800), \eta(1475) and X(1835). The exotic channels I=3/2 and I=1 are also considered. The former could be also resonant, in agreement with a previous prediction.

Speaker: Mr Miguel Albaladejo (U. Murcia)

93 Faddeev fixed center approximation to the NKbarK system and the signature of a N(1920)(1/2^+) state

We perform a calculation for the three body NKbarK scattering amplitude by using the fixed center approximation to the Faddeev equations, taking the interaction between N and Kbar, N and K, and Kbar and K from the chiral unitary approach. The resonant structures show up in the modulus squared of the three body scattering amplitude and suggest that a NKbarK hadron state can be formed. Our results are in agreement with others obtained in previous theoretical works, and reinforces the claim for a new N^* resonance around 1920 MeV with spin-parity J^P=1/2^+.

Speaker: Dr Ju Jun Xie (IFIC, University of Valencia)

94 Hadron production at finite temperature and density within an effective relativistic mean field model

We study the hadron yield ratios at finite value of baryon density and temperature by means of an effective relativistic mean-field model with the inclusion of the full octet of baryons, the Delta-isobars degrees of freedom and the lightest pseudoscalar and vector mesons. These last particles are considered in the so-called one-body contribution, taking into account of an effective chemical potential and an effective mass depending on the self-consistent interaction between baryons. The analysis is performed by requiring the Gibbs conditions on the global conservation of baryon number, electric charge fraction and zero net strangeness. In this context, we study the influence of the Delta-isobars degrees of freedom in the behavior of different hadron ratios and strangeness production.

Speaker: Andrea Lavagno (Politecnico di Torino)

95 Hadron Resonances within a Constituent-Quark Model

We present a microscopic model for hadron resonances which contains, in addition to constituent (anti)quarks, mesonic degrees of freedom. It is assumed that the (anti)quarks are confined by an instantaneous potential and that the mesons can couple directly to the (anti)quarks. This system is treated within a relativistic coupled-channel formalism in order to take the dynamics of the mesonic degrees of freedom fully into account. It is demonstrated that the mass eigenvalue problem for such a system can be reformulated as a purely hadronic eigenvalue problem in which bare hadrons, i.e. eigenstates of the pure confinement problem, are coupled via meson loops. The substructure of the bare hadrons is then hidden in (bare) hadron-meson vertex form factors. It is shown for a simple toy model that such a kind of approach may lead to reasonable (non-perturbative) decay widths for hadron resonances.

Speaker: Ms Regina Kleinhappel (Graz University)

96 Hadronization in Nuclei - Multidimensional Study

Hadron multiplicities in semi-inclusive deep-inelastic scattering were measured on neon, krypton and xenon targets relative to deuterium at an electron-beam energy of 27.6 GeV at HERMES. These ratios were determined as a function of the virtual-photon energy nu, its virtuality Q^2, the fractional hadron energy z and the transverse hadron momentum p_t with respect to the virtual-photon direction. Dependences were analysed separately for positively and negatively charged pions and kaons as well as protons and antiprotons in a two-dimensional representation. These results will help to constrain mechanisms and models of hadronization much more decisively than by the use of integrated results as traditionally done. A few features particular to the two-dimensional representation will be highlighted in this contribution. For example, at lower values of nu positive kaons do not show the typical rise of the multiplicity ratio with nu when z>0.4. In addition, protons were found to behave very differently from the other hadrons.

Speaker: Dr Inti Lehmann (University of Glasgow)

97 I=1/2 scalar meson in the lattice QCD

The resonance of scalar meson is reported to exist in $K-\pi$ system with a mass of about 800 MeV. This meson is called the kappa meson and may constitute the nonet scalar state together with the sigma meson. In the quark model, the mass of scalar meson should be in the higher region. It is very important to investigate the kappa meson by lattice QCD in order to establish the mass spectroscopy of the scalar mesons. Lattice QCD provides a first principal approach for hadron physics and allows us to study non-perturbative aspects of quark-gluon dynamics. We present our recent study of I=1/2 scalar meson by the lattice QCD simulation.

Speaker: Prof. Motoo Sekiguchi (Kokushikan University)

Paper MotooSekiguchi.zip

98 Measurement of the Pion Polarizabilities at COMPASS

At the COMPASS experiment located at the Super Proton Synchrotron (SPS) at CERN, several weeks of the 2009 beam time have been dedicated to the measurement of soft processes in the scattering of 190 GeV/c pions off nuclear targets. Primakoff Compton scattering pi- + Z ----> pi- + gamma + Z i.e. production of a real photon through interaction of the beam pion with a quasi-real photon from the Coulomb field of the nucleus can be separated from strong interactions by requiring extremely small recoil momenta and gives access to the pion polarizabilities alpha_pi and beta_pi and can be compared to predictions of chiral pertubation theory. The presentation will give an overview of the current state of analysis and include an outlook towards a high-statistics Primakoff beam time proposed for 2012. This work is supported by German Ministry of Education and Research, Cluster of Excellence 153 and Maier-Leibnitz-Labor Muenchen.

Speaker: Mr Thiemo Nagel (TUM)

99 Measurements of Bose-Einstein correlations at LHC with CMS

Bose-Einstein correlations between identical particles are measured in samples of proton-proton collisions at sqrt(s) = 0.9 and 7 TeV. The signal is observed in the form of an enhancement of number of pairs of same-sign charged particles with small relative momentum. The dependence of this enhancement on kinematic and topological features of the event is studied.

Speaker: Monika Grothe (U Wisconsin)

100 Nonet meson properties in Nambu Jona-Lasinio model with dimensional regularization

The Nambu Jona-Lasinio (NJL) model is one of the useful models of Quantum chromodynamics, and it describes observed meson properties nicely. In this talk, we study the nonet meson properties by using the NJL model with dimensional regularization at finite temperature and chemical potential. We find that the results of the meson properties show reasonable behaviors, which are similar to the ones obtained in the model with the frequently used cutoff regularization. This may indicate that the model predictions are not drastically affected by the difference between the regularization procedures in the NJL model.

Speaker: Dr Hiroaki Kohyama (Chung Yuan Christian University)

Paper kohyama.zip

101 On lepton pair production in proton-antiproton collisions at intermediate energies and the main backgrounds.

The lepton pair production in collisions of antiproton beam (E_beam = 14 GeV) with proton target is studied on the basis of event samples simulated with PYTHIA6 generator. Considered the quark level subprocess which goes through the production of virtual photon which converts into lepton pair (q qbar --> gamma* --> l+l-). The distributions of different kinematical variables which may be useful for the design of the muon system and the electromagnetic calorimeter of the detector of PANDA experiment at FAIR are presented. The analysis of these distribution shows the possibility to measure the proton structure function in a new kinematical region defined by the time-like values of the square of the momentum transferred 1 < Q^2 < 6.25 GeV^2 and withing a rather wide interval 0.05 < x < 0.7 of Bjorken x-variable. The problems due to the presence of fake leptons that appear from meson decays, as well as due to the background caused by minimum bias events and other QCD processes, are also discussed. The set of cuts which allows one to separate the signal events with lepton pairs from this kind of background events is proposed.

Speaker: Ms Anna Skachkova (JINR)

Paper Skachkova.tar

Poster POSTER_Munich2011.pdf

102 Possible hadronic molecules: Lambda_cN and Lambda_c-Lambda_c

Exotic heavy quark hadrons near one or several two-body thresholds triggered lots of discussions about hadronic molecule problem in the heavy quark sector. Here the larger reduced mass reduces the kinetic energy and is advantageous for the bound state. It is interesting to investigate possible molecules containing the lowest charmed baryon, Lambda_c (Lc). We present the study of two systems, Lc-N and Lc-Lc, in a one-boson-exchange potential model. The heavy quark symmetry leads to the nearly degenerate Sigma_c and Sigma_c^* and therefore the intermediate excited baryons may have important contributions to such systems. We explore these coupled channel effects. For our study, we first construct the effective Lagrangian reflecting the heavy quark symmetry, chiral symmetry, and hidden local symmetry and then derive the non-relativistic potentials. The numerical results are obtained by solving the Schrodinger equation. The coupling constants in the model are determined by decay of heavy baryons, quark model symmetry, chiral multiplet assumption, vector meson dominance assumption, and QCD sum rule results. To consider the extended structure of the hadrons, we introduce additional cutoff parameters at each vertex. Since we do not have enough information to determine the values, they are treated as free parameters. In studying the Lc-N system, we use both one-boson-exchange potential (OBEP) model and one-pion-exchange potential (OPEP) model. We find that the channel coupling is essential to the molecular bound states. Loosely bound molecules are obtained with the cutoff around 1.2~1.3 GeV in the OPEP model. To get molecule solutions, the cutoffs in the OBEP model can be smaller. In addition, both the binding energy and corresponding root-mean-square radius in the OMEP model may be roughly reproduced in the OPEP model. We use only the OPEP model in studying the Lc-Lc system. The channel coupling, especially the tensor force induced S-D wave mixing, plays a crucial role in binding two Lc's. According to our calculation, molecule-like solutions exist with the cutoff around 1.0~1.2 GeV. Tightly bound solutions with higher cutoffs may be beyond our model since shorter distance interactions contribute. To conclude, the molecular bound states in Lc-N and Lc-Lc are plausible, although the results are sensitive to the chosen cutoff parameters.

Speaker: Dr Yanrui Liu (Tokyo Institute of Technology)

Paper hadron2011-yrl.zip

103 Precise dispersive analysis of the f0(600) and f0(980) resonances from pion-pion scattering.

We extend the precise analysis of presently available pion-pion scattering data up to 1.1 GeV published in Phys.Rev.D83:074004,2011, by means of once subtracted Roy-like dispersion relations, twice subtracted Roy Equations, and Forward Dispersion Relations. The use of once-subtracted dispersion relations is essential to reduce uncertainties in the region around the K-Kbar threshold, whereas in the very low energy regime the strongest constraint comes from the standard Roy Eqs. Forward dispersion relations provide constraints up to roughly 1.4 GeV. Our results provide a precise and model independent description of the $f_0(600)$ and $f_0(980)$ regions together. In particular we show that the "dip-solution" for the elasticity is strongly preferred over the "non-dip" solution. We also provide final results for the resonance associated poles.

Speaker: Mr Jacobo Ruiz de Elvira (Universidad Complutense)

104 Prediction of Narrow N* and Λ* Resonances with Hidden Charm above 4 GeV

The interaction between various charmed mesons and charmed baryons is studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. Several meson-baryon dynamically generated narrow N* and Λ* resonances with hidden charm are predicted with mass above 4 GeV and width smaller than 100 MeV. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and can be looked for in the forthcoming PANDA/FAIR experiments.

Speaker: Mrs Raquel Molina (IFIC)

Poster poster2.pdf

105 Preliminary results on e^+e^- \to hadrons processes from SND detector at VEPP-2000 collider

Preliminary results on e^+e^- \to 3\pi, 4\pi, \omega \pi^0, \eta \pi^+\pi^-, N\bar{N} cross sections measured with SND detector at VEPP-2000 collider are reported. The data were collected in 2010-2011 in the energy range 2E = 1.0 - 2.0 GeV, the total integrated luminosity used is about 20 pb^{-1}.

Speaker: Mr Alexander Obrazovskiy (Budker Institute of Nuclear Physics)

Paper snd.tar

Poster SND.pdf

106 Properties of charm baryons in quark-diquark model

Study of the heavy flavour hadrons containing either a charm quark or a beauty quark has become a subject of recent interest due to the observations reported by the experimental groups at Belle, BABAR, DELPHI, CLEO, CDF etc;. Most of the new states observed in these experimental facilities are within the heavy flavour sector with one or more heavy flavour quark composition. In this paper, we present our study on the properties of single charmed baryons based on the quarkdiquark structure. The inter-quark potential is assumed as two body colour coulomb plus power potential with exponent, ν lying between 0.1 to 2.0. We find a strong correlation between the choice of the heavy quark mass parameter (mc), strong coupling constant (αs) and the potential exponent, (v) for getting the experimental mass spilt of ΔMΣc * −Σc= 64 MeV. The resultant spectroscopic parameters are used for computing magnetic moments, the electromagnetic radiative decay, strong hadronic decay and semileptonic decay widths of Σc, Λc systems. Numerical methods are employed for getting the spectra and the corresponding state vectors which are important inputs to study their decay properties. Our results for the choice of ν=1.0 and αs= 0.25 led to the fixing of charm mass parameter, mc= 1.5 GeV to have the experimental ΔMΣc * −Σc= 64 MeV [1]. With the same model parameters, we have computed the mass of Λc as MΛc = 2.293 GeV, as against the PDG2010 value of 2.286 GeV, the magnetic moment, μΛc = 0.395μN, as against the value of 0.380μN predicted in a relativistic quark model [2]. Our results for the transition decay width, ΓΣc→Λc γ = 72.77 MeV is close to 87.00 MeV predicted by Heavy Quark Symmetry [3] and the semileptonic width, ΓΛc→Λlνl = 0.83∗1011 S-1 is in good agreement with the PDG value of ΓΛc→Λlνl = 1.0∗1011 S-1 [1]. The overall agreement obtained in the present study indicates the success of the present model and the choice of the interquark potential for the description of the charm baryons. References: [1] K. Nakamura et al, PDG, J. Phy. G: Nucl Part. Phy. 37, 075021 (2010). [2] Amand Faessler et al, Phys. Rev. D 73, 094013 (2006). [3] S. Tawfiq et al, Phys. Rev.D 63, 034005 (2001).

Speaker: Mr Ajay Majethiya (Department of Physics, Sardar Patel University,)

Slides Germany_Hadron11.zip

107 Properties of rho and sigma mesons from unitarized Chiral Perturbation Theory.

We study the rho(770) and sigma(600) resonances by means of the Inverse Amplitude Method (IAM). The IAM is based on unitarity, analyticity and Chiral Perturbation Theory only and generates poles on the second Riemann sheet of pion-pion partial wave amplitudes associated to the resonances without any a priori assumptions on their existence or nature. In particular, we study the leading 1/N_c dependence of some resonance parameters to sheds light on their espectroscopic nature. The rho meson follows the expected qqbar scaling whereas we find a non qqbar dominant component for the sigma. We also study the m_\pi dependence of the resonance parameters to connect with lattice studies.

Speaker: Guillermo Ríos (Universidad Complutense de Madrid)

Paper hadron2011_Rios_poster.zip

108 Spectroscopy of the hadronic atoms and superheavy atoms: Energy shifts and widths and strong interaction corrections

In the last few years transition energies in pionic and kaonic atoms have been measured with an unprecedented precision [1]. The spectroscopy of hadronic hydrogen allows to study the strong interaction at low energies [2] by measuring the energy and width of the ground level with a precision of few meV. The light hadronic atoms can additionally be used to define new low-energy X-ray standards and to evaluate the pion mass using high accuracy X-ray spectroscopy. Paper is devoted to studying spectra for hadronic (kaonic and pionic) atoms and some superheavy isotopes. Ab initio QED approach [3] with an accurate account of relativistic, nuclear, radiative effects is used in calculating spectra of the hadronic (pion, kaon) atoms. One of the main purposes is establishment a quantitative link between quality of nucleus structure modeling and accuracy of calculating energy and spectral properties of systems. The wave functions zeroth basis is found from the Klein-Gordon or Dirac equation. The potential includes the SCF ab initio potential, the electric and polarization potentials of a nucleus (the RMF, Fermi and Gauss models for a charge distribution in a nucleus are considered). For low orbits there are the important effects due to the strong hadron-nuclear interaction. The energy shift is connected with a length of the hadron-nuclear scattering. For superheavy isotopes (ions) the correlation corrections of high orders are accounted for within the Green function method. The Lamb shift polarization part- in the Uhling-Serber approximation and the self-energy part – within the Green functions method. We present the data on: 1).energy levels for superheavy isotopes Z=113,114; 2). Shifts and widths of transitions (2p-1s,3d-2p, 4f-3d etc) in some pionic and kaonic atoms (H, He, N, W, U). The calculated X-ray transitions spectrum for kaonic He and estimate of 2p level shift due to the strong K-N interaction 1.57 eV are in the reasonable agreement with experimental data (cited shift 1.9eV) by Okada et al (2008; E570; КЕК 12GeV, RIKEN Nishina Centre, JAPAN) and differ (about order) of other experimental data by Wiegand-Pehl (1971), Batty et al (1979), Baird et al (1983). References: 1. D. Gotta, Progr. in Part. and Nucl. Phys. 52, 133 (2004); G. Beer, A. Bragadireanu, W. Breunlich et al, Phys. Lett. B 535, 52 (2002) ; R.Deslattes, E.Kessler, P.Indelicato, et al, //Rev. Mod. Phys. 75, 35 (2003); M.Trassinelli, P.Indelicato, arXiv:phys/0611262v2 (2007). 2. C.J.Batty, M.Eckhause, K.P.Gall etal//Phys.Rev.C. 40, 2154 (1989); T.Ito, R.Hayano, S.Nakamura, T.Terada, Phys. Rev. C. 58, 2366 (1998); S.Okada, G.Beer, H.Bhang etal, Phys.Lett.B.653, 387 (2007). 3. A.V.Glushkov et al, Phys. Lett. 170, 35 (1992) ; Frontiers in Quantum Systems in Chem. and Phys. (Berlin, Springer) 8, 505 (2008); Theory and Applications of Comp. Chem. (AIP) 1102, 168 (2009).

Speaker: Dr Olga Khetselius (Odessa University)

109 Stability of many quark systems

The problem of the stability of mesons and baryons against their decay into lighter hadrons has been widely discussed in the literature. During the last years it has been suggested the potential role played by higher-order many-quark configurations in the hadron spectra. These terms are a reflection of the involved color structure present in hadrons and they might be described either in terms of pairwise or non-pairwise interactions. Their stability against the decay into lighter mesons and baryons is an important spectroscopic ingredient. In this talk we focus on the role played by four- and six-quark configurations using both pairwise and non-pairwise interactions. Four-quark components are good candidates to describe some of the new measured states in the charm sector while the existence of six-quark states, either baryonium or baryon-baryon configurations, have been an ongoing matter of debate since the late seventies [1]. [1] T.F. Carames, A. Valcarce, J. Vijande, Phys.Rev.D82:054032,2010; Phys.Rev.Lett.103:222001,2009. J. Vijande, A. Valcarce, Phys.Rev.C80:035204,2009. J. Vijande, A. Valcarce, et al, Phys.Rev.D79:074010,2009; Phys.Rev.D76:114013,2007.

Speaker: Prof. Javier Vijande (university of Valencia)

110 Strong coupling constants of heavy baryons to pseudoscalar and vector mesons

The strong coupling constants of the heavy baryons to light pseudoscalar and vector mesons are calculated in light cone QCD sum rules. In particular, using the general form of the interpolating currents for the heavy baryons and distribution amplitudes of mesons as well as different symmetry arguments, all amplitudes in each class of transitions are written in terms of only one universal invariant function. Using the values obtained for the strong coupling constants, we also evaluate the decay rates of the corresponding strong transitions. A comparison of the obtained results with the existing predictions of the other nonperturbative approaches as well as experimental data is also made.

Speaker: Dr Kazem azizi (Dogus University)

111 Study of a0-f0 mixing at BESIII

The mixing intensity of f0(980) and a0(980) is expected to shed light on the nature of these two resonances. The a0-f0 mixing intensity has been predicted to be in the range of 0.01 to 0.2 by various theoretical models, but no any experimental results available yet. The transition of f0(980) to a0(980) or a0(980) to f0(980) will provide complementary constraints to the parameters of a0 and f0 mesons. Using the samples of 2.25X10^8 J/Psi events and 1.06X10^8 Psi' events collected with the BESIII detector, we perform direct measurements of a0-f0 mixing via the isospin breaking processes J/Psi-->\phi f0-〉\phi a0 and Chi_c1->pi0 a0->pi0 f0. The results on the a0(980)-f0(980) mixing intensity are presented.

Speaker: Ms Chunyan LIU (Institute of High Energy Physics)

112 STUDY OF DEUTERON-PROTON AND DEUTERON-DEUTERON COLLISIONS AT INTERMEDIATE ENERGIES

The $dp\to dp$ and $dd\to ^3He n$ reactions are considered in the energy range from few hundred MeV up to 1 GeV. The approach is based on the multiple-scattering theory, where the few-body collisions are presented through two-body ones. The high-energy nucleon-nucleon interactions are described by t-matrix, which is parameterized in accordance with the modern phase-shift analysis data. The special attention is given to investigation of the rescattering effects in these reactions. The theoretical predictions are obtained both for the differential cross sections and for the polarization observables, namely, vector and tensor analyzing powers. All results are presented in comparison with the existing experimental data.

Speaker: Dr Nadezhda Ladygina (JINR)

113 Test of OZI violation in vector meson production with COMPASS

The COMPASS experiment at CERN SPS completed its data taking with hadron beams ($p$, $\pi$, $K$) in the years 2008 and 2009 by collecting a large set of data on different targets ($H_2$, $Pb$, $Ni$, $W$). These data are dedicated to hadron spectroscopy, where the focus is directed to the search for exotic mesons and gluonic excitations. The production of such states is known to be favoured in glue-rich environments, $e.g.$ so-called OZI-forbidden processes. The OZI rule postulates that processes with disconnected quark line diagrams are forbidden. On the one hand, the study of the degree of OZI violation in vector meson production yields the possibilty to learn more about the involved production mechanisms while on the other hand it helps to understand the nucleon's structure itself. Contrary to former experiments, the large data sample allows for detailed studies in respect to both the four-momentum transfer $t$ and Feynman's variable $x_F$, respectively. We present results from the ongoing analysis on the comparison of the production of the vector mesons $\omega$ and $\phi$ in $p~p~\longrightarrow~p~(\omega/\phi)~p$, where the possibilty of measuring the spin alignment of both vector mesons at the same time makes COMPASS unique.

Speaker: Mr Johannes Bernhard (Institut f. Kernphysik, JGU Mainz)

Poster bernhard_OZI_hadron2011.pdf

114 The $\bar{K}NN$ system with chiral dynamics

We have performed a calculation of the scattering amplitude for the three body system $\bar{K}NN$ assuming $\bar{K}$ scattering against a $NN$ cluster, using the Fixed Center approximation to the Faddeev equations. The $\bar{K}N$ amplitudes, which we take from chiral unitary dynamics, govern the reaction and we find a $\bar{K}NN$ amplitude that peaks around 30-40 MeV below the $\bar{K}NN$ threshold, with a width in $|T|^2$ of the order of 50 MeV. The results are in line with those obtained using different methods but implementing chiral dynamics. The simplicity of the approach allows one to see the important ingredients responsible for the results.

Speaker: Dr Melahat Bayar (Instituto de Fisica Corpuscular)

115 The OLYMPUS experiment at DORIS/DESY

Measurements of the ratio of the electric and magnetic form factors of the proton yield different results when using the Rosenbluth or polarization transfer technique. This discrepancy has possibly been explained by two photon exchange that is not accounted for in the Born approximation. The OLYMPUS experiment will measure the ratio of the cross sections of elastic $e^-p$ and $e^+p$ scattering. Obtaining this ratio is a direct measurement of the two-photon contribution to the elastic $ep$ cross section and will significantly improve our understanding of the proton structure. An overview of the experiment and its current status will be presented in this talk.

Speaker: Jürgen Diefenbach (Universität Mainz)

116 The role of pion-exchange tensor forces in nuclear excitations

The pion play an important in recent theoretical models including the Effective Field Theory and the Constituent Quark Model with Goldstoune Exchange Interaction. Nucleon interactions within nuclei are considered as a result of one- and many-pion exchange. The role of tensor forces connected with the pion exchange in the description of nuclear binding energies and nuclear excitations was discussed recently by T.Otsuka, I.Tanihata, A.Arima and others. We performed the analysis of values of excitation in many nuclei which are situated at different parts of nuclear shells where tensor forces are important. We find out a systematic character of excitations and spacing in such nuclei by using recent compilation of nuclear excitations from Landoldt Bernstein Library vol I/25 Springer. Two the most frequently appearing stable energy excitation and intervals are found to be rationally connected with the pion and nucleon mass differences. This conclusion will be considered together with several the strongest correlations in the near-magic nuclei and in nuclei with the collective motions of nucleons.

Speaker: Dr Sergey Sukhoruchkin (Petersburg Nuclear Physics Institute)

117 The scalar form factor and the radius of the sigma meson

We calculate the sigma or f0(600) meson scalar form factor, i.e., its interaction with a scalar source. We make use of the knowledge that the sigma meson appears as a pole in pion-pion scattering. NLO Chiral lagrangians are used to calculate the interaction. Knowing the scalar form factor, we try to determine the scalar radius of the sigma meson.

Speaker: Mr Miguel Albaladejo (U. Murcia)

118 The Y(3940), Z(3930), and the X(4160) as dynamically generated resonances from the vector-vector interaction

We study the vector-vector interaction within the framework of the hidden gauge formalism for the channels with quantum numbers charm C=0 and strangeness S=0 in the energy region around 4000 MeV. By looking for poles in the complex plane we find three resonances that could be identified by the mass, width, and quantum numbers with the Y(3940), Z(3940), and X(4160), these poles appear with isospin I=0 and JPC=0++, 2++ and 2++, respectively. Whereas the Y(3940) and Z(3940) are coupled more strongly to D*D̅ *, the X(4160) is basically a Ds*D̅ s* molecular state. Another two extra resonances appear in our approach with I=0, 1 and JPC=1+-, 2++ which are not found in the PDG with masses M=3945, 3912 MeV and widths Γ=0, 120 MeV, respectively. In addition, the radiative decays of these hadrons will be mentioned.

Speaker: Mrs Raquel Molina (IFIC)

Paper proc_xyz.tar.gz

Poster poster3.pdf

119 Unprejudiced look at effective continuum thresholds in Borel dispersive sum rules

We show that the effective continuum threshold - one of the key parameters of the method of Borel sum rules for the calculation of properties of an isolated bound-state - is a complicated quantity. Although a constant approximation for the effective threshold is commonly used in the analysis of hadron observables within sum rules in QCD, the effective threshold in fact depends on the Borel parameter and for the case of the three-point function also on the momentum transfer. Moreover, the effective threshold which isolates the contribution of the ground state to a specific correlator turns out to vary from one correlator to another. We discuss an algorithm for fixing these thresholds which leads to a considerable improvement of the accuracy of the method of sum rules for the bound-state properties.

Speaker: Prof. Wolfgang Lucha (HEPHY Vienna Austria)

120 Weak decays of doubly-charmed baryons

We evaluate the weak decays of doubly-charmed baryons. We work in momentum space using the variational wave functions obtained in ref.[1]. We check our model results against heavy quark symmetry constraints. [1] C. Albertus et al., Eur. Phys. J. A 32, 183 (2007)

Speaker: Dr Eliecer Hernandez-Gajate (University of Salamanca)

Paper contribution.tex

Wednesday, June 15

Plenary Session: 5

Convener: Prof. Hartmut Wittig (Johannes Gutenberg-Universität Mainz)

121 News from hadrons in hot medium

Some of the modifications that a thermal medium, of the type generated in heavy ion collision experiments at the LHC, may impose on the properties of hadrons, are reviewed. The focus will be on hadrons including at least one heavy quark (c or b).

Speaker: Mikko Laine (Universität Bielefeld)

Slides hadron11.pdf

122 News from heavy-ion collisions (LHC and RHIC)

A new era has started in the field of relativistic heavy ion physics with lead beams delivered by the Large Hadron Collider (LHC) in November 2010. In this talk I will highlight main results from experimental measurements with Pb-Pb collisions at the incident energy of 2.76 TeV/nucleon recorded by LHC experiments. Recent experimental developments from the Relativistic Heavy Ion Collider (RHIC) at the GeV incident energy scale will be also discussed. All together LHC and RHIC measurements provide new insights on the properties and features of the new hot and dense form of matter created in the course of the relativistic heavy-ion collision.

Speaker: Dr Ilya Selyuzhenkov (EMMI/GSI)

Paper Proceedings_Hadron2011_Ilya_Selyuzhenkov.tar.gz

Slides 20110615_HADRON2011_IlyaSelyuzhenkov_v5.pdf

123 Review on results by the FLAG working group

We review lattice results relevant for pion and kaon physics with the aim of making them easily accessible to the particle physics community. We introduce quality criteria and use these when forming averages. Although subjective and imperfect, these criteria may help the phenomenologist to judge different aspects of current lattice computations.

Speaker: Dr Andreas Juettner (CERN)

Slides juettner_Hadron11_0611.pdf

124 Recent progress on effective field theories for hadron states

I will review some recent progress in our understanding of quarkonium at zero and finite temperature underlining the common theoretical framework that is at its basis.

Speaker: Antonio Vairo (Technische Universität München)

Slides hadron11.pdf

11:00 AM Coffee Break

Plenary Session: 6

Convener: Prof. Volker Metag (II. Physikalisches Institut)

125 Results on bottomonium and bottomonium-like production from the LHC

A new era of precision studies of the bottomonium family of states in hadron collisions, both proton-proton and heavy-ion, has opened up with the advent of the LHC. I present the first, already fully significant set of results from the LHC experiments, based on the initial LHC runs, and the prospects of forthcoming studies.

Speaker: Nuno Leonardo (Purdue University)

Slides 1_leonardo_bottomonium_hadron2011.pdf

126 Highlights from BESIII Experiment

The BESIII experiment had taken about 106 million psi(2S), 230 million J/psi events in 2009, and 0.92 fb-1 integrated lumimosity on psi(3770) peak for D physics in 2010. We are still collecting data at the psi(3770) this year, in this summer, we will have another 2.2 fb-1. The total luminosity on psi(3770) peak will be 3.1 fb-1, which is about four times of that at CLEO-c. The BESIII will go ahead to take data above open charm at 4010 MeV and 4170 MeV for Ds and XYZ(ccbar) states. I will present the most recent results and prespects for charm physics from the BESIII based on these data samples.

Speaker: Prof. Hai-Bo Li (Institute of High Energy Physics)

Slides 2_Highlight-BESIII-lihb.pdf

127 Hadrons in Nuclear Matter: sensors of the QCD vacuum ?

The talk addresses (i) the relation of QCD condensates and hadron spectral functions and their modifications in nuclear matter within QCD sum rules, and (ii) a hadronic transport-model description of the observed broadening of vector mesons traversing nuclei.

Speaker: Burkhard Kämpfer (Technische Universität Dresden)

Slides Kampfer_hadron2011_HZDR.ppt

128 Highlights from J-PARC Hadron Facility

J-PARC was almost competed in early 2009 and started the operational era. Nuclear and particle physics experiments are carried out in the Hadron Facility, one of three experimental facilities in J-PARC, using high-intensity secondary beams such as kaons, pions etc produced from 30 GeV proton beam. K1.8 beamline, one of four beamlines available in 2010, delivers mass separated charged particle beam up to 2GeV/c. Since high-resolution beam analyzer system and a large acceptance and high-resolution spectrometer, SKS, are equipped in the beamline, a lot of hypernuclear physics experiments, especially spectroscopy on S=-2 system, are planned. Among those experiments, pentaquark search (E19) was performed in 2010, as the first physics run in the Hadron Facility. Since the report on the discovery of the Theta+ by LEPS group [1], many positive results as well as negative one were reported. The existence of the Theta+ is not yet established so far. E19 was planned to confirm the existence of Theta+ and study production mechanism via the p(pi-,K-)X reaction with high missing mass resolution of ~1.5 MeV/c2 and high sensitivity of 75nb/sr at three incident momenta. We accumulated 16% of the aimed statistics in 2010 run at 1.92 GeV/c. In the talk, the latest analysis results will be presented. We will also the commissioning results of the beamline as well as physics program on hypernuclear and hadron physics at Hadron Facility.

Speaker: Prof. Toshiyuki TAKAHASHI (KEK)

Paper TTakahashi.tgz

Slides 4_Hadron2011TTakahashi.pdf

1:30 PM Lunch Break

3:00 PM Excursions

8:00 PM Conference Dinner

Thursday, June 16

Plenary Session: 7

Convener: Prof. Kamal K. Seth (Northwestern University)

129 Status of X, Y, Z states

We review the status of so called X, Y, Z states - charmonium-like states with many unusual properties observed in various experiments. Recent results of their studies at BaBar, Belle, Tevatron and LHC are discussed.

Speaker: Dr Simon Eidelman (Budker Institute of Nuclear Physics)

Slides 1_xyz11.pdf

130 Theory of X, Y, Z states

I briefly review the theory landscape for addressing the X,Y, and Z states, then discuss effective field theories for the X(3872), including the molecular hypothesis that takes advantage of the universal properties of states with large scattering lengths, emphasizing results that may clarify the character of the X(3872)

Speaker: Roxanne Springer (Duke University)

Slides springer.pdf

131 Production and Spectroscopy of Heavy Hadrons at the LHC

The early period of data taking at the LHC has been a very fruitful time for studies of heavy flavor production. The four large experiments - ALICE, ATLAS, CMS, and LHCb - have all made interesting measurements of charm and beauty production that are being compared to state-of-the-art predictions. First observations of new heavy flavor hadron decay modes are also emerging. I will review the status of these heavy flavor production and spectroscopy results, highlighting where we stand with respect to past measurements and predictions.

Speaker: Hal Evans (Indiana University)

Slides evans_hadron2011.pdf

132 Meson-baryon interactions and baryon resonances

Meson-baryon interactions are the fundamental building blocks to study baryon resonances and meson properties in few-body nuclear systems. We discuss the recent progress in the investigation of meson-baryon interaction in S=-1 sector and the structure of the Lambda(1405) resonance. In particular, we present a realistic KbarN-piSigma interaction in chiral dynamics constrained by the precise measurement of the kaonic hydrogen.

Speaker: Dr Tetsuo Hyodo (Tokyo Institute of Technology)

Slides 11_08Hadrons11_v3.pdf

11:00 AM Coffee Break

Plenary Session: 8

Convener: Eulogio Oset (IFIC , University of Valencia)

133 Highlights on hadron physics at CLAS

to be filled

Speaker: Kenneth H. Hicks (Ohio University)

Slides 1_Hadron2011-Hicks.pdf

134 Heavy-flavor baryons

While heavy-flavored mesons are a well-established laboratory for studying and testing QCD, much less is known about heavy-flavored baryons. In this talk the latest Tevatron results on heavy baryons are presented. These include an updated measurement of Sigma_b baryons, a Lambda_b branching ratio measurement, and a high-statistics study of charm baryons.

Speaker: Thomas Kuhr (Universität Karlsruhe)

Slides Kuhr.pdf

135 Baryon spectroscopy and resonances

The determination of the excited spectrum of baryons has been a major focus of experimental efforts worldwide. Spectroscopy reveals fundamental aspects of hadronic physics; however, the excited spectrum of light quark baryons is not well determined nor understood. Recent advances in lattice QCD calculations have enabled, for the first time, the determination of the highly excited spectrum of mesons and baryons. While these calculations are still in their early stages, there is some insight as to the nature of the highly excited nucleon and delta spectrum, both positive and negative parity. These recent calculations also demonstrate how resonant information, namely the mass and width, can be obtained. Many challenges remain, and the prospects for future work is described.

Speaker: Robert Edwards (JLAB)

Paper edwards_hadron2011.tar.gz

Slides edwards_hadron_11.pdf

1:00 PM Lunch Break

Future Experiments

Convener: Dr Bernhard Ketzer (TUM)

136 Future experiments

The talk discusses future experiments in hadron spectroscopy. It presents the physics motivation and the tools, accelerators and detectors, and reviews the status of the relevant projects, Belle-II/SuperKEKB at KEK, SuperB in Italy, PANDA at FAIR, and CLAS12 and GlueX at JLAB.

Speaker: Prof. Peter Krizan (University of Ljubljana)

Paper krizan.tar.gz

Slides 1_hadron2011-krizan.ppt

137 The Electron-Ion Collider at BNL

Nuclei and nucleons probed in DIS and diffractive processes in the high-energy (low-x) regime open a new precision window into fundamental questions in QCD. The proposed Electron-Ion Collider at BNL (eRHIC) is a new high-energy and high-luminosity polarized electron-ion/polarized proton machine. The proposed design provides unprecedented access to study deeply the nature of QCD matter and strong color fields. In particular, the new collider will allow us to reach and explore the regime where the gluon density saturates, one of the fundamental outstanding problems in QCD, and test the validity of the Color Glass Condensate approach. We will outline the compelling physics case for eRHIC focusing on e+A collisions and discuss briefly the status of the machine design.

Speaker: Dr J.H. Lee (Brookhaven National Laboratory)

Slides eRHIC_JHLee_Hadron11.pdf

138 LEPS2 GeV photon at SPring-8

The construction of a new backward Compton gamma ray beam line at SPring-8 in Japan, LEPS2, has been started from the year 2010. The new beam line will provide a highly polarized photon beam up to 3 GeV with 10 times higher intensity than that of LEPS1 facility. We will construct a 4$\pi$ detector which can detect both of charged particles and photons. The photon beam will be available from the year 2011, and a variety of hadron physics with strange quarks are planed. In this talk, the status of the construction of the LEPS2 facility and physics programs are reported.

Speaker: Dr Masayuki Niiyama (Kyoto Univ.)

paper hadron2011.tgz

Slides 3_hadron2011_niiyama.pdf

139 Search for Hadrons with Gluonic Excitations with GlueX

The GlueX experiment will employ a linearly polarized 9GeV tagged photon beam incident on a liquid hydrogen target to search for exotic states in the light meson spectrum. Optimized for this purpose, the detector has a highly uniform acceptance over nearly 4\pi solid angle, with high efficiency for both neutral and charged final state particles. An overview of the physics motivation and detector design will be presented.

Speaker: Igor Senderovich (University of Connecticut)

Paper hadron2011_GlueX_proc.pdf

Slides Search for Gluonic Excitations in Hadrons with GlueX

Light Baryons: 5

Spectroscopy and structure (formfactors, parton distributions functions, spin) of light baryons

Convener: Prof. Ulrike Thoma (HISKP. University of Bonn)

140 Pion scattering and electro-production on nucleons in the resonance region in chiral quark models

We present a method to calculate pion scattering and electro-production amplitudes in a coupled-channel framework incorporating quasi-bound quark-model states. All relevant low-lying nucleon resonances in the P33, P11, and S11 partial waves have been covered, including the Delta(1232), the N*(1440) and, most recently, the negative-parity resonances N*(1535) and N*(1650). The strong and electro-magnetic vertices of resonances are computed in the chosen quark model and not fitted. We show that even in a model as simple as the Cloudy Bag, a consistent description of the amplitudes can be achieved by using the same parameter set for all resonances. The meson cloud has been shown to play a major role, in particular in electro-magnetic observables for resonances in the P33 and P11 channels. However, the meson cloud is not strong enough to support quasi-bound states of baryons and mesons, as is the case in some models of N*(1440) and N*(1535). Consistent results were also obtained for the inelastic processes (two-pion, eta-N, and K-Lambda channels).

Speaker: Mr Simon Sirca (Faculty of Mathematics and Physics, University of Ljubljana)

Slides talk.pdf

141 Nucleon resonance electrocouplings from CLAS data on pion electroproduction

Studies of nucleon resonance electrocouplings for excited proton states at various photon virtualities Q2 represent an important part in the N* Program with the CLAS detector [1]. The CLAS measurements extend the data on differential cross sections for N\pi and N\eta electroproduction channels, longitudinally polarized beam/beam-target asymmetries for \pi electroproduction off protons considerably, providing a nearly complete coverage of the final hadron phase space. Electrocouplings of the P11(1440), D13(1520), and S11(1535) resonances were determined from analyses within the framework of two conceptually different reaction models [2] at Q2 from 0.3 to 5.0 GeV2, and at Q2 from 0.3 to 6.0 GeV2 for the P33(1232) state. Data were also collected on charged double pion electroproduction off protons leading to nine independent differential \pi+\pi-p cross sections [3]. Using a phenomenological approach [4] allowed us to establish all essential mechanisms contributing to this channel at invariant masses of final hadrons W less then 1.8 GeV, and Q2 up to 1.5 GeV2. The P11(1440) and D13(1520) electrocouplings were determined from the \pi+\pi-p electroproduction data for the first time. They are in a good agreement with the results of the independent N\pi electroproduction analyses [2], offering evidence for the reliable extraction of resonance electrocouplings. First results from the \pi+\pi-p electroproduction channel on electrocouplings of S11(1650), D33(1700), and P13(1720) resonances have also become available. Analyses of these results in quark models and evaluation of the N* meson-baryon dressing [5] strongly suggests two contributions to \gamma{v}NN* electrocouplings: a) an internal quark core, and b) an external meson-baryon cloud. A further extension of the N* Program with the CLAS12 detector after completion of JLAB 12 GeV Upgrade Project will be outlined. References. 1. I.G.Aznauryan, et al., arXiv:1102.0597 (2011). 2. I.G.Aznauryan, et al., Phys. Rev. C80, 055203 (2009). 3. G.V.Fedotov, et al., Phys. Rev. C80, 015204 (2009). 4. V.I.Mokeev, et al., Phys. Rev. C80, 045212 (2009). 5. B.Julia-Diaz, et al., Phys. Rev. C77, 045205 (2008).

Speaker: Dr Victor Mokeev (Jefferson Lab)

Slides Hadron11_mokeeev.pdf Hadron11_mokeeev.pptx

142 Covariant electroweak structure of light and strange baryons

We present covariant predictions for all electromagnetic and axial form factors of baryon ground states with flavors up, down, and strange, as calculated from the relativistic constituent quark model with Goldstone-boson-exchange hyperfine interactions. In addition we give the theoretical values for electric radii, magnetic moments, and axial charges. In all cases, where a comparison to experiment is possible, the theoretical results are in good agreement with the existing phenomenological data. In other cases we may compare to modern results from lattice quantum chromodynamics. Here too, a surprisingly good agreement is found.

Speaker: Mr Ki-Seok Choi (Graz Univ)

Paper Hadron2011_Proceedings-kschoi.zip

Slides 3_Choi_Hadron2011.pdf

Light Mesons: 4

Spectroscopy and decay of light mesons

Convener: Prof. Volker Crede (Florida State University)

143 Hadron Spectroscopy at CLAS

The g12 experimental period (April - June 2008) at the CEBAF Large Angle Spectrometer (CLAS) at Jefferson Laboratory was a high-luminosity photon run at the highest CEBAF energies. A tagged bremsstrahlung beam was available between 1.2 and 5.7 GeV with a raw integrated luminosity of 68 pb$^{-1}$, 27 pb$^{-1}$ in the high energy range greater than 4.4 GeV. The principal aim of the experiment is the study of exotic hadrons, that is mesons and baryons outside of the naive quark model, in particular hybrid mesons and pentaquark baryons. However, an open trigger has produced a rich dataset to examine a range of photo-produced phenomena. Here we report on the current status of the analysis, which includes the study of meson and baryon spectroscopy including strangeonia in the meson sector, and cascade and Y* resonances in the baryon sector. The high luminosity has also permitted the study of spectroscopy through rare channels. The superb electron/positron detection at CLAS has also permitted the study of vector mesons through the rare $e^+e^-$ decay, as well as the study of the Dalitz decay mode of the $\pi^0$, $\eta$, and $\eta$'.

Speaker: Dr Dennis Weygand (Jefferson Laboratory)

Slides 1_weygand.pdf

144 Light Vector Meson Photoproduction off of H at Jefferson Lab and ρ-ω Interference in the Leptonic Decay Channel

Recent studies of light vector meson production in heavy nuclear targets has generated interest in ρ-ω interference in the leptonic decay channel. An experimental study of the elementary process provides valuable input for theoretical models and calculations. In experiment E04-005, high statistics photoproduction data has been taken in Jefferson Lab’s CLAS detector with tagged photon energies up to 5 GeV incident on a LH2 target. Preliminary results of the e+e− decay channel, with emphasis on the ρ-ω interference region, will be shown and compared to similar experimental data of photoproduction off of heavier nuclear targets (2H to Pb) from Jefferson Lab experiment E01-112.

Speaker: Prof. Chaden Djalali (University of South Carolina)

Paper C_Djalali_Contribution.tgz

Slides 2_C_Djalali_Hadron2011.pdf

145 Resonances and their Nc fates in U(3) chiral perturbation theory

We first present the full one-loop calculation of meson-meson scattering in the framework of U(3) chiral perturbation theory with explicit resonance states in the Lagrangian. After the partial wave projection and resummation of the unitarity loops, we fit our theoretical formulas to the data to fix the free parameters and then calculate the resonance pole positions and residues, such as rho(770), K*(892), phi(1020), sigma, f0(980), f0(1370), a0(980), a0(1450), kappa, K*0(1430). The Nc trajectories of these resonance poles are specially paid attention to in this work, since this is the first time in the literature that the pseudo-Goldstone nature of the singlet eta_1 in large Nc limit is considered in determining the resonance Nc properties.

Speaker: Dr Zhi-Hui Guo (Universidad de Murcia)

Slides 3_Guo-hadron2011.pdf

146 Quark mass dependence of meson-meson resonances and phase shifts within standard and unitarized ChPT

We report on our recent results [1] in the study of the chiral extrapolation of the phase-shifts in elastic pion-pion scattering, using both standard and unitarized ChPT to one and two loops. In the standard ChPT approach, limited to low momenta, we study the S, P and D waves. For the vector phase shift we find a behavior that would seemingly contradict the results of lattice and other effective theories, but that can be explained with a very simple model. In fact, the calculations using the IAM to unitarize the amplitudes reconcile these "strange" behavior at low energy with what is expected intuitively for this channel. The unitarization extends the analysis to energies of around 1 GeV, being compatible with standard ChPT at low energies for the S and P waves. The D waves cannot be generated to this order with this method. When comparing with lattice results in the I=2 channel phase shifts, we find an agreement of standard ChPT below 200 MeV up to pion masses of 400-450 MeV, and a nice improvement beyond 200 MeV when using the IAM. We have also performed a Montecarlo analysis to provide an estimation of the uncertainties. We also report on the results [2] on the strange and light quark mass dependence of the light resonances reproduced within the IAM approach in SU(3) to one loop. The scalar resonances, sigma and kappa, are shown to behave very differently than the vector resonances, rho and K*, which has to be taken into account in the lattice studies. [1] J. Nebreda, J. R. Pelaez, G. Rios, arXiv:1101.2171. To appear in Phys. Rev. D (May 2011). [2] J. Nebreda and J. R. Pela´ez, Phys. Rev. D 81, 054035 (2010).

Speaker: Jenifer Nebreda (Universidad Complutense de Madrid)

Slides Nebreda_Hadron11.pdf

Quarkonia: 4

Production, spectroscopy, and decay of quarkonia

Convener: Mikihiko Nakao (KEK)

147 Exotic gifts of nature

We perform a systematic analysis of doubly charmed exotic states as meson-meson molecules [1]. We compare our results with those previously obtained within the hyperspherical harmonic formalism[2]. Several relevant conclusions have to be emphasized. First of all, the conclusive existence of a stable isoscalar doubly charmed meson with quantum numbers $(I)J^P=(0)1^+$. This state could be considered as a {\it gift of nature}, because there is compelling evidence that such large mass exotic states could be efficiently produced via gluon-gluon fusion at LHC with unique signatures in the detectors and also at RHIC. Second, we revise hadron-hadron scattering calculations within the quark model showing that they have to be done in a complete Hilbert space. The effects coming from the inclusion of the relevant vectors of the Hilbert space could be hidden in the parameters of the model, but this would make that the calculations were not predictive because the parameters have to be different for each quantum number sector. Such a procedure would drive to spurious conclusions. Third, the discovery of these states will undoubtedly give an important push in our understanding of the meson spectroscopy above the threshold for the production of two mesons. Finally, our study highlights the difficulty to generate deeply bound states within the quark model framework when dealing with the threshold and the many-quark system on the same footing. An experimental effort in this direction will confirm or rule out the theoretical expectations. If the scenario presented here turns out to be correct, it will open a new interesting spectroscopic era. [1] T.F. Caramés, A. Valcarce, and J. Vijande; Phys. Lett. B in press (2011). [2] J.Vijande, A. Valcarce, and N. Barnea, Phys. Rev. D 79, 074010 (2009).

Speaker: Dr Javier Vijande (Univ. Valencia)

148 New results on charmonium and charmonium-like systems at Belle

We present the results of recent charmonium studies with the Belle experiment. These studies include the determination of eta_c and eta_c(2S) parameters in B decays and new results on X(3872), including its radiative decays, mass and width determination, angular analysis for its quantum number determination.

Speaker: Dr Sören Lange (Universität Giessen)

Slides talk_HADRON2011.pdf talk_HADRON2011.ppt

149 Charmonium and Charmonium-like States with BABAR

We present a search for the X(3872) produced in B-->psi pi+pi- K and B-->psi pi+pi-pi0 K (psi=J/psi or psi(2S)) using 427 fb-1 of BaBar data. We present updated mass and width measurements for the Y(4260)--> J/psi pi+pi- produced in Initial State Radiation events using 454 fb-1 of data. We report the study of the B meson decays B+--> J/psi phi K+ and B0--> J/psi phi K_S, and of charged and neutral B decays to chi_c1 K pi. We describe a detailed study of charmonium states produced in two-photon collisions and decaying to K_S K pi and K K pi pi pi0. We present a high statistics measurement of the mass and width of the etac(2S) state.

Speaker: Valentina Santoro (INFN Ferrara)

Slides 3_Hadron2011v3.pdf

150 Molecular effects in Charmonium Spectrum

The discovery of the $J/\psi$ meson in 1974 was the experimental confirmation of the existence of the charmed quark introduced theoretically in 1970 by Glashow, Iliopoulus and Maiani to explain the cancellation of loop diagrams in $K^0$ weak decays. Consisting of a charmed $c$ quark and a $\bar c$ antiquark the $J/\psi$ particle became the starting point of a whole family of bound states called charmonium. A further milestone in the knowledge of the charmonium structure began in 2002 with the new data coming from high luminosity experiments at B factories. Since then more than ten new states have been observed, most of them being difficult to understand in a quark-antiquark framework. Meson-antimeson molecular states may represent an alternative explanation to these states. Meson-antimeson pairs containing one heavy and one light quark can exchange pions which may contribute to bind the system. In Ref.~[1] we have performed a calculation of the $X(3872)$ state as a $DD^*$ molecule in the framework of a constituent quark model [2]. The one pion exchange interaction is not enough to bind the system and only when we mix the molecular state with the $\chi_{c1}(2P)$ $q\bar q$ pair we get the $X(3872)$ as a bound state. The original $\chi_{c1}(2P)$ $q\bar q$ state adquires a significant $DD^*$ component and can be identified with the $X(3940)$. Following these ideas we have started a program to study the influence of possible molecular structures in the charmonium spectrum. Based on the formalism developed by Baru et al. [3], we perform a coupled channel calculation in which the mass and the width of the resonances can be determined nonperturbatively. The interactions in the molecular channels are calculated using the Resonating Group Method and the $q\bar q$ interaction of Ref.~[2]. Two and four quark states are coupled through the $^3P_0$ mechanism . We focus on the $0^{++}$ and $1^{--}$ sectors. In the first one, coupling the $DD$,$J/\psi \omega$, $D_s D_s$ and $J/\psi \phi$ channels to the ^$2^3P_0$ $q\bar q$ pair we obtain two states compatibles with the $X(3915)$ and the $Y(3940)$ mesons . In the $1^{--}$ sector we include the $3^3S_1$ and $2^3D_1$ charmonium states coupled to $DD$, $DD^*$, $D^*D^*$, $D_sD_s$, $D_sD_s^*$ and $D_s^*D_s^*$. In this calculation we obtain the controversial Y(4008) as a new molecular state and two $c\bar c$ states dressed by molecular components. One important outcome of the calculation is that the new $\psi(4040)$ has a bigger probability of $2^3D_1$ state and the $\psi(4160)$ of the $3^3S_1$ state. To test this new structure, we calculate the decay branching ratios measured by BABAR [4]. As already notice the result using the bare states are in clear disagreement with the experiment while we find a good agreement for the couple channel calculation. \item{[1]} P. G. Ortega, J. Segovia, D. R. Entem, F. Fern\'andez, \emph{Phys. Rev.} \textbf{D81}, 054023 (2010) \item{[2]} J. Vijande, F. Fernández, A. Valcarce, J. Phys. G 31, 481 (2005). \item{[3]} V. Baru et al. Eur.Phys. J. A44 93 (2010) \item{[4]} B. Aubert et al., Phys. Rev. D 79, 092001 (2009)

Speaker: David Rodriguez Entem (University of Salamanca)

Paper paper.tgz

Slides entem.pdf

4:00 PM Coffee Break

Hadrons in Hot and Cold Medium: 3

Heavy ions, mesons in nuclei, and hypernuclei

Convener: Prof. Wolfram Weise (Technische Universität München)

151 Pseudoscalar mesons in nuclei and partial restoration of chiral symmetry

I would like to discuss pseudoscalar mesons, especially pion, in a context of partial restoration of chiral symmetry in nuclear medium. First of all, I show a general relation between the in-medium quark condensate and hadronic quantities in nuclear medium. With this relation, we can confirm that partial restoration of chiral symmetry takes place in nuclei based on experimental observations of deeply bound pionic atom states. I would like to discuss briefly also kaonic few body systems, in which kaons and nucleons form quasibound states. Finding similarity between the interactions antikaon-kaon and antikaon-nucleon, we see systematics of three-body systems of antikaons, kaons and nucleons.

Speaker: Dr Daisuke Jido (Kyoto University)

Slides 1_-_Hadron2011_Jido.pdf

152 eta'(958) bound states in nuclei and Partial Restoration of Chiral Symmetry

The study of the spontaneous breaking of chiral symmetry and its partial restoration at finite density based on the studies of the Mesic Atoms and Mesic Nuclei is one of the important branch of modern Hadron Nuclear Physics [1,2]. We try to proceed this research field to investigate the U_A(1) anomaly effects in the nuclear medium by studying the eta'(958) Mesic nuclei. The present exploratory level of the U_A(1) anomaly effects at finite density is rather poor since there exists no experimental information on the possible effective restoration of the U_A(1) anomaly in nucleus, though some theoretical results have been reported long ago [3,4]. Since the huge eta'(958) mass is believed to have a very close connection to the U_A(1) anomaly, the eta'(958) mass in the medium should provide us with important information on the effective restoration of the U_A(1) anomaly. In this context, the eta'(958) mesic nuclei is considered to be one of the most interesting systems [5,6]. We report two important points in this talk; (i) the possible existence of the quasi-stable eta'(958) bound states with significantly small decay widths, and (ii) the theoretical predictions for the formation of the eta'(958) mesic nuclei relevant to the actual experiments. The possibility of the existence of the quasi-stable states is theoretically considered recently [7]. The eta'(958) mass is considered to be generated by the U_A(1) anomaly which picks up the chiral condensate around to give the extra mass for eta'(958). Hence, we expect the mass reduction of the eta'(958) at finite density because of the reduced condensate there. In this talk, we point out the possibility to have no (or small) imaginary part of the selfenergy accompanied by the mass reduction mechanism through the U_A(1) anomaly. As the consequence, we have the possibility to have strong attractive interaction with small imaginary part between eta'(958) and nucleus, which ensures us to have quasi-stable eta'(958) bound states. We will also report the expected formation spectra of the eta'(958) mesic nuclei. We have made the comprehensive predictions for the formation by the photon [5,6] and pion [8] beams using the Green's function methods. [1] K. Suzuki $et$ $al$., Phys. Rev. Lett. 92, 072302 (2004). [2] D. Jido, T. Hatsuda, and T. Kunihiro, Phys. Lett. B670, 109 (2008). [3] R. D. Pisarski and F. Wilczek, Phys. Rev. D29, 338 (1984). [4] T. Kunihiro, Phys. Lett. B219, 363 (1989). [5] H. Nagahiro and S. Hirenzaki, Phys. Rev. Lett. 94, 232503 (2005). [6] H. Nagahiro, M. Takizawa and S. Hirenzaki, Phys. Rev. C74, 045203 (2006). [7] D. Jido, H. Nagahiro, S. Hirenzaki, in preparation. [8] H. Nagahiro, Prog. Theor. Phys. Suppl. 186, 316 (2010).

Speaker: Prof. Satoru Hirenzaki (Nara Women's University)

Slides 2_-_Hadron2011.Munich.pdf 2_-_Hadron2011.Munich.ppt

153 Production and study of baryons with beauty at the Italian heavy flavour factory (SuperB)

The SuperB factory, whose construction was recently approved by the Italian government, is an asymmetric heavy flavour factory where e+, e- beams will collide with a peak luminosity in excess of 10^36 cm-2 s-1 at the Y(4S) resonance c.m. energy. The Y(4S) then decays in BBbar meson pair with a B.R. > 96%, thus allowing, among other topics, a systematic study of B-meson decays. While for B-mesons a large set of experimental results exists, few data are available for B-baryons. The reason for this lack of information is essentially experimental: B-baryons cannot be abundantly produced with a mechanism similar to the one exploited for B-mesons, neither at electron, proton or ion colliders, nor in fixed target experiments. However, thanks to its high luminosity, SuperB would offer a unique opportunity to indirectly produce huge quantities of B-baryons via a "beauty exchange" mechanism. Indeed, if for instance a B- meson is let to impinge on a nuclear target, the following reaction can occur: B- + N(bound) --> Lambda0_b + pi (1) where N(bound) indicates a nucleon inside a nucleus. With a similar "beauty exchange" mechanism Sigma_b and Sigma_star_b are accessible as well through reactions similar to (1). Production of Xi0_b and X0_b baryons, via the B- + N(bound) --> Xi_b + K, is at the limit of the available phase space for a free nucleon, while Omega_b is out of reach. Moreover the SuperB features allow to reach a production yield for the above reactions very close to 100%, provided that the low beta-gamma B- mesons will brought to rest in very thin targets before decaying. The study of B-baryons decay modes can be performed with the same SuperB companion apparatus. The only additional stuff is just a thin target installed inside the beam pipe and as close as possible to the interaction point without, of course, interfering with the circulating beams. The really reduced transverse dimensions of the beams at the I.P. (few microns) allows for such an arrangement. The target, made of any suitable solid material, can have a rectangular prism or a cylindrical (both sector and full) shape. By keeping in mind that for B c_tau is ~ 0.5 mm, the target inner surface could be placed at a distance of ~ 0.2 mm from the beam axis and its thickness could be of the order of 0.3 mm. As far as the longitudinal dimension is concerned, a 10-15 mm total length should full the needs of the described measurement. Such a device should be cooled and should be remotely operated in order to be moved away from the beam axis by exploiting, for instance, the technique routinely used for the DAFNE collider scrapers.

Speaker: Dr Alessandro Feliciello (INFN - Sezione di Torino)

Paper AFeliciello@Hadron2011.zip

Slides AFeliciello@Hadron2011.pdf AFeliciello@Hadron2011.ppsx

154 In-medium properties of the omega meson near the production threshold

Using the CrystalBall/TAPS photon spectrometer at MAMI Mainz the omega photoproduction off nuclei (C, Nb) and off the proton (LH2) were studied via the hadronic decay channel gamma + A -> omega + X -> pi0 gamma + X. The aim of this work is to investigate whether the properties of the omega meson are modified within normal nuclear matter. Two different experimental approaches have been used: the measurement of the omega lineshape and of the omega momentum distribution. Different in-medium scenarios [1] calculated with the GiBUU transport code [2] predict only small differences in the omega lineshape. The momentum distribution of the omega meson is, however, predicted to be more sensitive to in-medium modifications. Differences are expected to be most pronounced close to the production threshold (E_gamma,thresh = 1108 MeV). Thus, the analyses were performed in the energy ranges 900 to 1300 MeV and 900 to 1100 MeV. The experimental results for the omega lineshape and the omega momentum distribution will be presented and compared to GiBUU calculations. Supported by DFG(SFB/TR16) [1] J. Weil, private communication [2] http://gibuu.physik.uni-giessen.de

Speaker: Dr Michaela Thiel (II. Physikalisches Institut, JLU Giessen)

Paper Proceeding_MThiel_Hadron2011.zip

Slides MThiel_hadron2011_medium3.pdf

155 Internal structure of resonant Lambda(1405) state in chiral dynamics

The internal structure of the resonant Lambda(1405) state is investigated based on meson-baryon coupled-channels chiral dynamics, by evaluating density distributions obtained from form factors of the Lambda(1405) state. The form factors and the density distributions are defined as an extension of the ordinary stable particles and are directly evaluated from the meson-baryon scattering amplitude, paying attention to the gauge invariance of the probe interaction. For the resonant Lambda(1405) state we find that the resonant Lambda(1405) state is composed of widely spread antikaon around nucleon, which gives dominant component inside Lambda(1405), with escaping pi Sigma component. Also the validity of our formulation for the form factors is investigated from a pure bound state, and it is found that the form factor in our approach serves as a natural generalization of the form factor for stable particles.

Speaker: Dr Takayasu Sekihara (Tokyo Institute of Technology)

Paper hadron2011_Sekihara.zip

Slides 5_-_110616_Hadron11_Sekihara.pdf

Heavy Hadrons: 4

Spectroscopy and decay of heavy hadrons

Convener: Dr stefano bianco (Laboratori Nazionali di Frascati dell'INFN)

156 Measurements of inclusive B-quark production at 7 TeV with the CMS experiment

Measurements performed by the CMS experiment of the cross section for inclusive b-quark production in proton-proton collisions at sqrt(s) = 7 TeV are presented. The measurements are based on different methods, such as inclusive jet measurements with secondary vertex tagging or selecting a sample of events containing jets and at least one muon, where the transverse momentum of the muon with respect to the closest jet axis discriminates b events from the background. The results are compared with predictions based on perturbative QCD calculations at leading and next-to-leading order.

Speaker: Paolo Bellan (Univ. di Padova e Sez. dell'INFN)

Slides 1_Hadron11_Bellan.pdf

157 Measurement of exclusive B-hadron production at 7 TeV with the CMS experiment

Measurements of the total and single differential cross sections for B+, B0, Bs mesons and Lambda_b baryons produced in pp collisions at sqrt{s}=7 TeV are presented. The results are compared with predictions based on perturbative QCD calculations at leading and next-to-leading order

Speaker: Hans-Christian Kaestli (Paul Scherrer Institut)

Slides ExclusiveB_CMS.pdf

158 Measurement on B-hadron angular correlations at 7 TeV with the CMS experiment

A measurement of the angular correlations between beauty and anti-beauty hadrons produced in LHC pp collisions at sqrt{s}=7 TeV is presented, probing for the first time the small angular separation region. The B hadrons are identified by the presence of secondary vertices from their decays and their kinematics reconstructed combining the decay vertex with the primary interaction vertex. The results are compared with predictions based on perturbative QCD calculations at leading and next-to-leading order.

Speaker: Christophorus Grab (ETH Zürich)

Slides CGrab_Hadron2011_fin.pdf

159 Studies of open heavy flavour production at LHCb

The data collected by LHCb in 2010 have been used to study the production of charm and beauty hadrons in pp collisions at sqrt(s) = 7 TeV. Differential cross-sections will be presented and compared with theoretical predictions. Results will also be shown on production asymmetries, and the relative fractions of B_s and Lambda_b production. If available, updates will also be shown using 2011 data.

Speaker: Artur Ukleja (Andrzej Zoltan Institute for Nuclear Studies, Warsaw)

Paper Proceedings_au.zip

Slides 20110616_AU_Hadron2011.pdf 20110616_AU_Hadron2011.pptx

160 Weak B Decays into Orbitally Excited Charmed Mesons

Accuracy on the measurement of the Cabbibo - Kobayashi - Maskawa matrix elements demands a detailed knowledge of semileptonic decays of b -hadrons. In particular, decays involving orbitally excited c-mesons provide an important contribution to the total semileptonic width. Therefore, a better understanding of these processes will reduce the uncertainties in the above mentioned matrix elements. Moreover B and Bs meson weak decays into Ds(2317) and Ds(2460) open charm mesons can provide further information about the nature of these controversial states. Recently, BaBar Collaboration has re- ported [1] a study of B semileptonic decays into nal states containing charged and neutral D1(2420) and D*2(2460), the two narrow orbitally-excited charmed light mesons. Moreover the Belle Collaboration has measured [2] the branching fractions of the non leptonic decay B -> DS1(2536) multiplied by that of DS1(2536) -> D*K. They also calculate different ratios involving B decays into Ds(2317) and Ds(2460) mesons. From a theoretical point of view these processes involve two steps: a weak decay of the B meson and a strong decay of the charmed meson. The matrix elements for semileptonic decays can be parametrized in terms of form factors which, within the spectator approximation, can be evaluated from the wave functions of the mesons involved in the decay [3]. We evaluate these wave functions using the Constituent Quark Model of Ref. [4] which successfully describes hadron phenomenology and reactions. Strong decay widths are calculated consistently within the same model using a 3P0 and a microscopic model, where the strong decay is driven by the same interquark potential which determines the meson spectrum. In the case of the semileptonic decays, the theoretical results agree reasonably with the experimental values. The prediction obtained with the microscopic model is closer than those obtained with the 3P0 model. Comparison of our results with the prediction of heavy quark symmetry is also included. Motivated by our good previous results about semileptonic B decays into P-wave charmed mesons we have extend our work to the exclusive B decays into P-wave charmed-strange mesons. Preliminary results suggest a more complicate structure than a simple q\bar{q} pair for some of these mesons. [1] B. Aubert et al. (BaBar Collaboration), Phys. Rev, Lett. 103, 051803 (2009). [2] T. Aushev et al. (Belle Collaboration), Phys. Rev. D 83, 051102 (2011) [3] E. Hernandez, J. Nieves and J. M. Verde-Velasco, Phys. Rev. D 74, 074008 (2006). [4] J. Vijande, F. Fernandez, and A. Valcarce, J. Phys. G 31, 481 (2005).

Speaker: Mr Jorge Segovia (Universidad de Salamanca)

Paper ID122_Segovia.tar.gz

Slides JSegovia_weak_HADRON2011.pdf

Light Mesons: 5

Spectroscopy and decay of light mesons

Convener: Prof. Paul Eugenio (Florida State University)

161 The Search for Exotic Mesons in $\gamma p\to\pi^+\pi^+\pi^-n$ with CLAS at Jefferson Lab

\par In addition to ordinary $q\bar{q}$ pairs, quantum chromodynamics (QCD) permits many other possibilities in meson spectra, such as gluonic hybrids, glueballs, and tetraquarks. Experimental discovery and study of these exotic states provides insight on the nonperturbative regime of QCD. Over the past twenty years, some searches for exotic mesons have met with controversial results, especially those obtained in the three-pion system. Prior theoretical work suggests that in photoproduction gluonic hybrids might be found at enhanced levels relative to that found in pion production. To that end, the E004-05 experiment at Jefferson Lab's CEBAF Large Acceptance Spectrometer (CLAS) has recently acquired a high statistics photoproduction dataset, using a liquid hydrogen target and tagged photons from a 5.71 GeV electron beam. The CLAS experimental apparatus was modified to maximize forward acceptance for peripheral production of mesons. The resulting data contains the world's largest 3$\pi$ photoproduction dataset, with $\gamma p \to \pi^+\pi^+\pi^-n$ events numbering in the millions. Partial-wave analyses are underway in search of the exotic $J^{PC} = 1^{-+}$ $\pi_1(1600)$, and preliminary fit results from these studies will be shown.

Speaker: Craig Bookwalter (Florida State University)

Slides exotics_in_photoproduction_clas.pdf

162 Study of the reaction pi- Be -> pi-pi-pi+eta Be in the VES experiment.

The Partial-Wave analysis of the reaction: pi- Be -> pi-pi-pi+eta Be with E_beam = 28 GeV is performed in full 4-body mesonic final state phase-space. In the wide range of momentum transfer t' = 0.-1. GeV/c^2 the dominance of diffractive-like (natural-parity exchange) mechanism is demonstrated. The individual partial waves in f1(1285) pi-, eta'pi- and a2(1320) eta systems are discussed. There is no evidence of eta(1295) pi- production. Various interpretations of PWA results are suggested.

Speaker: Dr Dmitry Ryabchikov (Institute for High Energy Physics)

Slides 2_ryabchikov_hadron2011_ves.pdf

163 The Exotic $\eta'\pi^-$ Wave in $190\,\textrm{GeV}$ $\pi^-+p\to\eta'+\pi^-+p$

From COMPASS 2008 data a sample of 40,000 events of the type $\pi^-p\to\eta'(\to\eta(\gamma\gamma)\pi^+\pi^-)\pi^-p_{\textrm{slow}}$ with $-t>0.1\,\textrm{GeV}^2/c^2$ was selected for a partial-wave analysis. Monte Carlo simulations display a smooth dependence of the acceptance on kinematic variables. Study of the alternative final state with $\eta\to\pi^+\pi^-\pi0(\gamma\gamma)$ provides a check of the procedure. The goal of this analysis is to compare the relative strengths of the $\eta'\pi$ $P_+$-, $D_+$- and $G_+$-waves to those observed at VES and BNL at lower bombarding energies. In those analyses, unnatural parity transfer is strongly suppressed. We study the evolution to COMPASS energies of the known broad $P_+$-wave intensity and its phase motion relative to the $D_+$-wave near the $a_2(1320)$ mass and with respect to a broad $D_+$-wave structure at higher mass. The $t$-dependence is studied in detail. The results are compared to those obtained for other 2-pseudoscalar channels.

Speaker: Mr Tobias Schlüter (LMU Munich)

Slides etaprime_presentation_schluter.pdf

164 Some properties of light scalar mesons in the complex plane

Some properties of the scalar mesons sigma(600) and f0(980) are discussed using the Roy integral equations to control continuations in the complex energy plane. On the real axis, firstly, high precision numerical solutions of the equations are constructed for energies up to the K-Kbar threshold. Fits to the data by such solutions are performed and constrained by the recent measurements of the S-wave scattering lengths by the NA48/2 collaboration. These results are combined with recent measurements of photo-photon scattering to two pions by the Belle collaboration. From a chirally constrained analytic representation of the amplitudes, the values of the couplings of the sigma(600) and f0(980) to two photons are deduced. As a second application, the question of the gluon and q-qbar "contents" of the scalar mesons is reconsidered. These may be defined using analytic extensions to the second sheet of two-point correlators of GG and q-qbar operators. The pole residues involve pion-pion matrix elements of these operators. A numerical evaluation is made using dispersion relations and low-energy constraints.

Speaker: Dr Bachir Moussallam (IPN Orsay)

Slides cxscalar.pdf

165 Spectra of Light and Heavy Mesons, Glueball and QCD Effective Coupling

The spectroscopy of light- and heavy-quark mesons as well as the lowest-state glueball state are investigated within a relativistic quantum-field model based on analytical confinement. Ladder Bethe-Salpeter-type equations are derived to define the spectra of quark-antiquark and two-gluon bound states. We provide a new analytic estimate of the lowest-state glueball mass and calculate spectra of some light, intermediate and heavy mesons in a wide range of energy scale $\sim 0.1-10$ GeV [1]. The QCD effective coupling $\alpha_s$ is studied by exploiting the conventional meson spectrum. A new, independent and specific infrared-finite behavior of QCD running coupling is found below $\sim 1$~GeV [2]. By introducing only a minimal set of parameters (the quark masses and the confinement scale) we obtain results in reasonable agreement with recent experimental data. We demonstrate that global properties of some low-energy phenomena may be explained reasonably in the framework of a simple relativistic quantum-field model if one guesses correct symmetry structure of the quark-gluon interaction in the confinement region and uses simple forms of propagators in the hadronization regime. Refs: [1] G.Ganbold, Phys.Rev., D79, 034034 (2009) [2] G.Ganbold, Phys.Rev., D81, 094008 (2010)

Speaker: Dr Gurjav Ganbold (Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Russia)

Paper Contribution (6 pages)to the Hadron2011 conference proceedings from Ganbold

Slides 5_ganbold_HADRON2011f.pdf

Quarkonia: 5

Production, spectroscopy, and decay of quarkonia

Convener: Dr Bernhard Ketzer (TUM)

166 Exotic spectroscopy and quarkonia at LHCb

The last ten years have seen a resurgence of interest in exotic spectroscopy driven by the discovery of the X(3872) in the J/ψππ spectrum. Searches and studies of exotic quarkonia form an important part of LHCb's physics programme. We present results for the production of ψ(2S) and χc(1,2) in the dimuon plus pions or photon channels, as well as the first results for X(3872) production using the dataset collected in 2010, which corresponds to about 34 pb–1. A measurement of the X(3872) mass in the J/ψππ mode together with production properties will be presented. The ψ(2S) production in the same decay channel and the χc2/χc1 cross-section ratio will also be discussed, together with future prospects on these measurements at LHCb.

Speaker: Mr Bo Liu (Center for High Energy Physics, Tsinghua University)

Slides Exotic_spectroscopy_and_Quarkonia_at_LHCb_Hadron2011.pdf

167 Observation of the X(3872) state with the CMS experiment

A measurement of the ratio of $X(3872)$ and $\psi(2S)$ signal yields in $pp$ collisions at 7 TeV is presented, using data recorded at the CMS experiment in 2010 corresponding to an integrated luminosity of 36pb-1. The events are reconstructed decays into $J/\psi \pi^+ \pi^-$ and subsequent decay of the $J/\psi$ candidates into two muons. The measured ratio is compared to theoretical expectations.

Speaker: Jian Wang (Institute of High Energy Physics)

Slides hadron2011_cms_jianwang.pdf

168 Quarkonia Measurements with ALICE at the LHC

ALICE is the dedicated heavy-ion physics experiment at the Large Hadron Collider (LHC). It is designed to provide excellent capabilities to study the Quark-Gluon Plasma (QGP), the deconfined state of strongly-interacting matter, in the highest energy density regime opened up by the LHC. Quarkonia, bound states of heavy (charm or bottom) quarks such as the J/ψ, are crucial probes of the QGP in A-A collisions. High-precision data from p-p collisions are an essential baseline for measurements in A-A, and moreover, serve as a crucial test for competing models of quarkonium hadroproduction. ALICE measures quarkonia down to pt = 0 via their decay channels into e+e− in the central barrel detectors (|y| < 0.9) and into μ+μ− in the muon spectrometer (2.5 < y < 4.0). We will present first results on the transverse momentum and rapidity distributions of the inclusive J/ψ production cross section in p-p collisions. The polarisation of J/ψ and the dependence of the J/ψ yield on the charged particle multiplicity in √s = 7 TeV p-p collisions will be discussed. Finally, results on the inclusive J/ψ production in √sNN = 2.76 TeV Pb-Pb collisions, the nuclear modification factor RAA and the central-to-peripheral modification factor RCP will be shown.

Speaker: Mr Frederick Kramer (IKF Uni Frankfurt)

Slides fkramer_slides.pdf

169 Heavy quarkonium spectrum and width in a weakly-coupled quark-gluon plasma

We develop a Non-Relativistic Effective Field theory approach for heavy quarkonium at finite temperature. Such a framework is based on the T=0 one of NRQCD and pNRQCD. Within this approach we calculate the heavy quarkonium energy levels and decay widths in a quark- gluon plasma whose temperature is much smaller than the inverse radius of the bound state. This is achieved by subsequently integrating out the scales that characterize the system, creating a series of EFTs. Relevance for the phenomenology of heavy ion collisions is also discussed.

Speaker: Mr Jacopo Ghiglieri (TUM)

Slides ghiglieri_hadron2011.pdf

Friday, June 17

Hadrons in Hot and Cold Medium: 4

Heavy ions, mesons in nuclei, and hypernuclei

Convener: Prof. Tomofumi Nagae (Kyoto University)

170 Hypernuclei Production by K- at rest

The creation of a hypernucleus requires the injection of strangeness into the nucleus. This is possible in different ways, mainly using a π+ or a K− beam on fixed targets. A complete review of hypernuclei production by K- at rest will be presented. When a K- stops inside a nucleus it can undergo the so called "strangeness-exchange reaction", in which a neutron is replaced by a Lambda with the emission of a pion. By precisely studying the outgoing pions both the binding energy and the formation probability of the hypernuclei can be measured. New measurements from the FINUDA experiment on Li7, Be9 and C13, coupled with previous measurements on C12 and O16, allowed for the first time the study of the formation of hypernuclei as a function of the atomic mass number A. The new measurements also offered the possibility of disentangling the effects due to atomic wave-function of the captured K− from those due to the pion optical nuclear potential and from those due to the specific hypernuclear states. These new results on the study of the hypernuclei production by K- at rest will also be presented and discussed.

Speaker: Germano Bonomi (University of Brescia and INFN Pavia)

Slides 1_bonomi-kStopHypernuclei.pdf

171 Experimental studies of mesic nuclei at J-PARC

A pseudoscalar meson may be bound in a nucleus, if the interaction between the meson and the nucleon is attractive enough. In particular, the possible existence of kaonic nuclei attracts both experimentalists and theorists in these days. Two experimental groups, FINUDA and DISTO, claim the observation of K-pp bound states in different reactions, although hot debate with regard to the existence of deeply-bound K-pp states is still going on. Two experiments with secondary meson beam will be carried out in near future at J-PARC. The E15 experiment will utilize the (K-, n) reaction on liquid 3He target, whereas the J-PARC E27 experiment will investigate the (pi+, K+) reaction on liquid deuterium target. A characteristic decay mode of K-pp into Lambda+p will be tagged in both the experiments so as to reduce irrelevant backgrounds. By the way, it is also known that an eta meson and a nucleon is weakly attractive. The eta-nucleus interaction has been investigated by use of near-threshold eta production. An alternative way to assess the strength of the interaction is to measure the binding energy and the decay width of eta-mesic nuclei, if they do exist. Such an experiment may be possible with pion beam at J-PARC, as well as MAMI (photon beam) and COSY (proton/deuteron beam). In this contribution, the author will introduce experimental programs at J-PARC, focusing on kaonic nuclei and eta-mesic nuclei.

Speaker: Dr Hiroyuki Fujioka (Kyoto University)

Paper hadron2011.pdf

Slides 2_hadron2011_fujioka_v2.pdf

172 Probing cold nuclear matter with virtual photons

Recently the HADES collaboration has extended its physics program from heavy ion collisions to proton induced reactions in order to investigate cold nuclear matter effects. Therefore we did two experiments, p+p and p+Nb, focusing on the modification of the spectral function in the rho/omega meson invariant mass region. Compared to previous measurements the high acceptance of the HADES detector allows for a detailed analysis of e+e- pairs with low momenta relative to the medium, where predicted modifications of the spectral functions of vector mesons are believed to be most prominent. Comparing slow and fast e+e- pairs from the same data sample we find a strong difference in the shape of the spectral distribution in the whole vector meson region pointing towards a significant reduction of the omega yield around its pole mass for slow pairs and an enhanced contribution from rho and Delta decays.

Speaker: Michael Weber (University of Houston, Texas, USA)

Paper pNb_mweber_hadron2011.tgz

Slides pNb_hadron2011_v3.pdf

173 Neutral kaon production in $p + p$ and $p + Nb$ collisions

Kaon interaction with baryonic matter is characterized by a repulsive potential according to common belief. However, the values of the measured potential are not yet consistent with each other. We analyze the kaon in-medium behavior employing $K^{0}_{S}$'s identified with the HADES detector in p+p and p+Nb collisions at 3.5 GeV kinetic beam energy. The comparison of the $K^{0}_{S}$ differential cross sections in p+Nb and p+p collisions provides access to the in-medium kaon potential at normal nuclear matter density. The distinctive feature of our measurements is a high-statistics sample of kaons with low transverse momenta ($p_{t} < 100$ MeV$/c$), ensuring the sensitivity to the nuclear matter effects. We present the data analysis method and first results.

Speaker: Mr Kirill Lapidus (Excellence Cluster "Universe")

Paper hadron11_lapidus.tar

Slides 4_lapidus_hadron.pdf

Heavy Hadrons: 5

Spectroscopy and decay of heavy hadrons

Convener: Prof. Stephan Paul (TU-München)

174 HEAVY BARYON SPECTRUM, NEW HEAVY EXOTICS AND ISOSPIN BREAKING

discuss several highly accurate theoretical predictions for masses of baryons containing the b quark which have been recently confirmed by experimental data. I point out that proper treatment of the color-magnetic hyperfine interaction in QCD is crucial for obtaining these results. Several yet untested predictions are given for additional properties of heavy baryons. The same approach applied to the X(3872) meson suggests that it is a tetraquark and leads us to propose a novel mechanism for the strong violation of isospin observed in its decays. I also discuss the implications of the two charged exotic resonances with quantum numbers of a (b bar u dbar) tetraquark, very recently reported by Belle in the channel [Upsilon(nS) pi+, n=1,2,3].

Speaker: Prof. Marek Karliner (Tel Aviv University)

Paper karliner_hadron2011.pdf karliner_hadron2011.tar.gz

Slides 1_karliner_heavy_bayons_and_exotics_hadron2011.pdf

175 Baryon bound states of three hadrons with charm and hidden charm

In this work, we show our recent theoretical results for three-body systems in the charm sector which are made of three hadrons and contain one nucleon, one D meson and in addition another meson, Dbar, K or Kbar. The Fixed Center Approximation to the Faddeev equations was used, in which we take a cluster of two particles and allow the third one to interact with either of the constituents of the cluster. The cluster wave function as well as the interaction of its components with the the third particle are obtained using two body interaction amplitudes from the chiral unitary approach. In all cases, NDDbar, KDN and KbarDN system, we find a three body bound state with hidden charm and open charm respectively. The states have J^P=1/2^+ and massed around 4400 MeV, 3080 MeV and 3150 MeV respectively. The widths are very small for the first two cases (less than 10 MeV) and about 50 MeV for the last state.

Speaker: Mr Chu-Wen XIAO (Departamento de Fisica Teorica and IFIC, Universidad de Valencia)

Slides Baryon_bound_states_of_three_hadrons_with_charm_and_hidden_charm(_Chu-Wen_Xiao,Melahat_Bayar,Eulogio_Oset).pdf

176 Heavy hadron spectroscopy and production at ATLAS

ATLAS has studied heavy flavor production and measured the production cross sections of heavy quarkonia, open bottom and charm. Differential cross sections as a function of transverse momentum and pseudorapidity will be presented. ATLAS capabilities to reconstruct heavy quarkonium states, D-mesons and B-hadrons in exclusive decay modes will be demonstrated.

Speaker: Carlo Schiavi (INFN Genova)

Paper hadron2011.tar.gz

Slides ATLAS-HeavyHadron.pdf

177 Effective Quark-Quark Interaction in Heavy Baryons

We report first results from a study of heavy-baryon spectroscopy within a relativistic constituent-quark model whose hyperfine interaction is based on Goldstone-boson-exchange dynamics. While for light-flavor constituent quarks it is now commonly accepted that the effective Q-Q interaction is (predominantly) furnished by Goldstone-boson exchange, due to spontaneous chiral-symmetry breaking of QCD at low energies, there is currently still much speculation about the light-heavy and heavy-heavy Q-Q interactions. With the increasing amount of experimental data on heavy-baryon spectroscopy these issues might soon be settled. Here, we show, how the relativistic constituent-quark model with Goldstone-boson-exchange hyperfine interactions can be extended to charm and bottom baryons. It is found that the same model that has previously been successful in reproducing the light and strange baryon spectra is also in line with the existing phenomenological data on heavy-baryon spectroscopy. An analogous model with one-gluon-exchange hyperfine interactions for light-heavy and/or heavy-heavy flavors does not achieve a similarly good performance.

Speaker: Mr Joseph Day (University of Graz)

Paper Joseph_Day_-_Munich_Contribution.zip

Slides J_Day_Munich.pdf

178 Heavy Hadron Spectroscopy and Production at Tevatron

Using the data collected with the CDF and DZERO detectors running at the Tevatron the measurements of the charm and bottom hadrons will be presented. We will talk in details about recent CDF measurements of heavy baryon properties of charmed Sigma_c and Lambda_c* and of their bottom partners, Sigma_b. The CDF results on exotic Y(4140) state will be discussed. The new production measurement of a bottom baryon Lambda_b with the DZERO detector will be described.

Speaker: Dr Igor GORELOV (University of New Mexico, USA)

Slides gorelov-id237.pdf

Light Mesons: 6

Spectroscopy and decay of light mesons

Convener: Dr Claude Marchand (CEA IRFU/SPhN Saclay)

179 First results from VEPP2000 collider in Novosibirsk

Regular data taking is going on in Novosibirsk at VEPP2000 e+e- collider. Two new (or significantly modified) detectors a in operation at two available interaction region. Luminosity up to 10**31 has been reached so far, limited by positron source. First 1-2 GeV c.m. energy scan has been performed and first preliminary results on e+e- -> hadrons, barions are demonstrated by two detector teams.

Speaker: Prof. Evgeny Solodov (Budker INP)

Slides 1_Solodov_VEPP2000.pptx

180 Diffractive Dissociation into 3 Pion Final States at COMPASS

Diffractive dissociation reactions studied at the COMPASS experiment, CERN, provide access to the light meson spectrum. During a pilot run in 2004, using a pion beam and a lead target, 500k events of pi- pi- pi+ final state events with masses below 2.5 GeV/c^2 were recorded, yielding a significant signal for the p1(1600) spin-exotic resonance. After a significant upgrade of the spectrometer in 2007, the following two years were dedicated to meson spectroscopy. Using again a pion beam, but now with a liquid hydrogen target, an unique statistics of ~100M events of the same final state was gathered in 2008. During a short campaign in 2009, the liquid target was exchanged by several solid state targets in order to compare final states produced on targets with different atomic numbers. After a short summary of a partial wave analysis (PWA) of 2004 data, the focus will be on a PWA of 2008 data in the same kinematic range of momentum transfer (0.1 GeV^2/c^2 < t’ < 1.0 GeV^2/c^2). In addition the progress of the analysis of data recorded with solid state targets in 2009 and a comparison with 2008 and 2004 data will be presented.

Speaker: Mr Florian Haas (Physik-Department E18 Technische Universität München)

Slides fhaas_HADRON2011.pdf

181 Spin-exotic search in the $\rho\pi$ decay channel: First results on $\pi^{-}\pi^{0}\pi^{0}$ in comparison to $\pi^{-}\pi^{+}\pi^{-}$ final states (diffractively produced on proton)

The COMPASS experiment at CERN SPS features charged particle tracking as well as good coverage by electromagnetic calorimetry, and our data provide excellent opportunity for simultaneous observation of new states in different decay modes in the same experiment. The existence of the spin-exotic $\pi_1(1600)$ resonance in the $\rho\pi$ decay channel is studied for the first time in COMPASS in both decay modes of the diffractively produced $(3\pi)^{-}$ system: $\pi^{-}p \rightarrow \pi^{-}\pi^{+}\pi^{-}p$ and $\pi^{-}~p \rightarrow \pi^{-}\pi^{0}\pi^{0}~p$. A preliminary partial-wave analysis performed on the 2008 proton target data allows for a first conclusive comparison of both $(3\pi)^{-}$ decay modes not only for main waves but also for small ones. We find the neutral versus charged mode results in excellent agreement with expectations from isospin symmetry. Both, the intensities and the relative phases to well-known resonances, are consistent for the neutral and the charged decay modes of the $(3\pi)^{-}$ system. The status on the search for the spin-exotic $\pi_1(1600)$ resonance produced on a proton target is discussed.

Speaker: Dr Frank Nerling (University of Freiburg)

Slides nerling_hadron2011.pdf

182 Hadronic resonances made of multi-vector mesons

In previous works regarding the interaction of two vector mesons using the techniques of the chiral unitary approach, it was shown that the vector-vector interaction in s-wave with spins aligned is very strong both for rho-rho and K*-rho to the point to get dynamically the f2(1270) and K*2(1430) resonances. In the work presented in this talk we use the rho-rho and rho-K* interaction in spin 2 and isospin 0 channel to show that the resonances rho3(1690), f4(2050), rho5(2350) and f6(2510) and the strange $K^*_2(1430)$, $K^*_3(1780)$, $K^*_4(2045)$, $K^*_5(2380)$ and a not yet discovered $K_6^*$ are basically molecules of increasing number of rho(770) mesons (with also a K*(892) in the case of the strange states). We use the fixed center approximation of the Faddeev equations to write the multi-body interaction in terms of the two-body scattering amplitudes. We find the masses of the states very close to the experimental values.

Speaker: Dr Luis Roca (University of Murcia)

Slides proceeding_roca.tar.gz Roca.pdf

183 Mixing properties of a1(1260) meson consisting of hadronic composite and quark composite

We propose a practical method to clarify the mixing nature of hadrons consisting of multiple components having different origins, by demonstrating an analysis of the a1(1260) meson [1]. One of recent interests in hadron structure is whether hadrons are made up of quarks as described in the conventional quark model, or develop subcomponents of quark-clusters inside. One good example is provided by the a1(1260) axial vector meson. The a1 meson is a candidate of the chiral partner of the rho meson and can also appear as a gauge boson of the hidden local symmetry [2], which is recently reconciled in the holographic QCD [3]. On the other hand, in coupled-channel approaches based on the chiral effective theory, the a1 meson has been described as a dynamically generated resonance in the pi-rho scattering [4,5]. In this study, we regard the a1 meson as a mixed state of the quark-composite (we refer to it as the elementary component) and the hadronic composite and propose a method to disentangle their mixture appearing in the physically observed state. As an extension, we apply our method to the study of the large Nc behavior of the a1 state and discuss the limitation of the classification for such a mixed state. [1] H. Nagahiro, K. Nawa, S. Ozaki, D. Jido, A. Hosaka, e-print arXiv:1101.3623 [hep-ph]. [2] M. Bando, T. Kugo, and K. Yamawaki, Phys. Rept. 164(1988)217. [3] T. Sakai, and S. Sugimoto, Prog. Theor. Phys. 114(2005)1083. [4] L. Roca, E. Oset, and J. Singh, Phys. Rev. D72(2005)014002. [5] M. F. M. Lutz, and E. E. Kolomeitsev, Nucl. Phys. A730(2004)392.

Speaker: Prof. Hideko Nagahiro (Nara Women's University)

Paper files.tar.gz

Slides hadron2011_nagahiro.pdf

184 New observations on hadron spectroscopy at BESIII

With samples of 220 million $J/\psi$ events and 110 million $\psi^\prime$ events collected in the BESIII detector, $p\bar{p}$ mass threshold enhancement is studied. The enhancement is evident in $J/\psi$ radiative decay, which is consistent with BESII result. No significant narrow enhancement is observed in $\psi^\prime$ radiative decay. For $J/\psi\rightarrow\gamma\pi^+\pi^-\eta^\prime$ decay, the $X(1835)$, which was previously observed by BESII, is confirmed with a statistical significance that is larger than $20\sigma$ and the angular distribution of the radiative photon is consistent with expectations for a pseudoscalar. In addition, in the $\pi^+\pi^-\eta^\prime$ invariant mass spectrum, the $X(2120)$ and the $X(2370)$, are observed with statistical significances larger than ~$7.2\sigma$~ and ~$6.6\sigma$~, respectively. A new process $J/\psi\rightarrow\omega X(1870)\rightarrow\omega a_0\pi$ is also observed in $J/\psi\rightarrow\omega\pi^+\pi^-\eta$ decay.

Speaker: Ms Hongwei LIU (Institute of High Energy Physics)

Slides 6_LIUHongwei_hadron2011.pdf

Low-Energy Processes: 2

Non-resonance physics

Convener: Dr Jan Friedrich (TUM)

185 Chiral dynamical aspects of recent low energy reactions measured at MAMI, ELSA, GRAAL, and other labs

Recently, eta photoproduction on the neutron has received intense experimental interest at GRAAL, ELSA and MAMI due to the appearance of a sharp structure at around W=1670 MeV. We show that this peak can be explained conventionally within coupled channels chiral dynamics. Also, predictions for the I^s and I^c and other polarization observables in the related gamma p --> pi0 eta p reaction, measured at MAMI, ELSA, GRAAL and other labs, will be presented. This reaction helps shed light on the meson-octet baryon-decuplet interaction in chiral dynamics.

Speaker: Michael Döring (Forschungszentrum Jülich)

Paper My proceedings for the Hadron 2011 conference. Contains contribution.tex + .eps-files. Please let me know if you need a different format. Thanks, Michael

Slides Hadron_2011_Doring.pdf

186 Renormalization of Spin-Flavor Van der Waals Forces

In analogy with atomic physics and using the quiral quark model we derive a Nucleon-Nucleon (NN) potential in the Born-Oppenheimer approximation at second order in perturbation theory where the $\Delta$ resonance is included implicitly [1,2]. This NN potential turns out to be singular at short distances with a van der Waals like behavior and hence needs to be renormalized. In fact, the short distance behavior is identical to the one of Chiral Two-Pion-Exchange (ChTPE) potentials [3,4] being moreover the mid-range attraction for both schemes very similar to each other. This provides a simpler alternative to the widely used ChTPE potentials where NN properties can be calculated. We show results for central waves and the deuteron and then the correlation between different partial waves [5] is applied to obtain higher partial waves phase shifts with a lower number of counter-terms and a better description in general. We also calculate the electromagnetic (EM) form factors of the deuteron and finally the possible implications for Nuclear Physics are analyzed. [1] Renormalization and Universality of NN interactions in Chiral Quark and Soliton Models. E. Ruiz Arriola and A. Calle Cordon, e-Print: arXiv:0910.1333 [hep-ph] [2] Renormalization of spin-flavor van der Waals forces. A. Calle Cordon and E. Ruiz Arriola (in preparation) [3] Peripheral NN scattering: Role of delta excitation, correlated two pion and vector meson exchange. Norbert Kaiser, S. Gerstendorfer, W. Weise. Nucl.Phys.A637:395-420,1998. [4] Nuclear forces with Delta-excitations up to next-to-next-to-leading order. I. Peripheral nucleon-nucleon waves. Hermann Krebs, Evgeny Epelbaum, Ulf-G. Meissner. Eur.Phys.J.A32:127-137,2007. [5] Renormalization of chiral two pion exchange NN interactions with Delta-excitations: Correlations in the partial wave expansion. M. Pavon Valderrama, E. Ruiz Arriola. e-Print: arXiv:1005.0744 [nucl-th]

Speaker: Dr Alvaro Calle Cordon (Jefferson Lab)

Paper arXiv identifier for my contribution is 1108.5992 available at: http://arxiv.org/abs/1108.5992

Slides Cordon_Hadron2011.pdf

187 The pp \to p Lambda K+ and pp \to p Sigma0 K+ reactions with chiral dynamics

We report on a theoretical study of the pp \to p Lambda K+ and pp \to p Sigma0 K+ reactions near threshold using a chiral dynamical approach. The production process is described by single-pion and single-kaon exchange. The final state interactions of nucleon-hyperon, K-hyperon and K-nucleon systems are also taken into account. We show that our model leads to a fairly good description of the experimental data on the total cross section of the pp \to p Lambda K+ reaction. We find that the experimental observed strong suppression of Sigma0 production compared to Lambda production at the same excess energy can be explained. In addition we obtain the scattering length and effective range for the Lambda p interaction.

Speaker: Dr Hua-Xing Chen (IFIC, Valencia University)

Paper hadron2011chen.tar.gz

Slides hadron2011(Chen).pdf

188 pi- gamma -> pi-pi-pi+ at low masses compared to ChPT prediction at COMPASS

COMPASS is a multi-purpose fixed-target experiment at CERN SPS, that investigates the structure and spectroscopy of hadrons. Dissociation of pions on nuclear or hydrogen targets provides clean access to the light meson spectrum. During a short run with 190 GeV/c pi- beam on lead in the year 2004, about 4 million exclusive pi-pi-pi+ events have been collected. For the 3 million events with low momentum transfer t'<0.01 (GeV/c)^2, coherent scattering off the nucleus as a whole can be assumed, with contributions from Reggeon (Pomeron) and photon exchange. For the lowest t'<0.001 (GeV/c)^2, the electromagnetic interaction part becomes apparent. The status of the partial-wave analysis of these data will be presented, focussing on new techniques for the extraction of the contribution from photon exchange at low masses. Its measured absolute cross-section is compared to ChPT calculations.

Speaker: Stefanie Grabmüller (TU München)

Slides grabmueller_3pic_chpt.pdf

189 Study of interference of Coulomb and strong diffractive production of pi-pi-pi+ systems produced off Pb target at COMPASS

The reaction pi-Pb->pi-pi-pi+Pb with E_beam = 190 GeV is studied in great detail by Partial-Wave analysis methods. The low momentum transfer region t' < 0.01 GeV/c^2 shows the dominance of coherent diffraction production mechanism and also clear contribution of Coulomb production. For several M=1 amplitudes the intensities as functions of t' demonstrate very sharp peaks near zero, characteristic for photon exchange, while phase motions as functions of t' show significant variation which reflects the interference of Coulomb and strong processes. Theoretical description of measured intensities and phases can provide precise separation of Coulomb contribution (and thus give better measurement of a2(1320) radiative width as an example) as well as better knowledge of absolute phase of strong diffractive amplitude (and so properties of the pomeron regge trajectory).

Speaker: Dr Dmitry Ryabchikov (Institute for High Energy Physics)

Slides 5_ryabchikov_interference.pdf

190 Study of Ke4 decays at NA48 and ChPT tests

The NA48/2 collaboration has accumulated ~45000 semi-leptonic K charged decays to pi0 pi0 e+- neutrino (Ke400), increasing the world available statistics by more than two orders of magnitude. Low background contamination and very good pi0 reconstruction bring the first precise measurement of the Branching Fraction and decay Form Factor at the percent level. Concurrently, more than one million K charged decays to pi+ pi- e+- neutrino (Ke4+-) have been analyzed, leading to an improved determination of the Branching Fraction by a factor of 3 and detailed Form Factor studies. Comparison of both Ke4 modes decay properties allows a test of chiral symmetry relations and ChPT predictions at unprecedented level.

Speaker: Mauro Piccini (University of Perugia)

Slides 6_HADRON2011_piccini.pdf 6_HADRON2011_piccini.ppt

Technologies

Convener: Boris Grube (Technische Universität München)

191 Partial Wave Analysis using Graphics Cards

Partial Wave Analysis (PWA) is a key tool in hadron spectroscopy. Besides raising difficult questions as to what physics models to use and how to interpret results, it also poses superb challenges in computing, especially with the large statistics samples available today at facilities like BES III or COMPASS and in the future at GLUE X and PANDA. I discuss the use of parallel computing, especially the harnessing of Graphics Processing Units (GPUs) for PWA and review the history of these attempts from first trials four years ago to several mature software frameworks in use today.

Speaker: Dr Niklaus Berger (IHEP)

Slides Talk.pdf

11:00 AM Coffee Break

Plenary Session: 9

Convener: Prof. Aleksandr Mikhailovich Zaitsev (IHEP Protvino)

192 Review of Hyperons in Nuclei

In these 20 years, hypernuclear physics has been developed at KEK-PS, BNL-AGS and JLab-CEBAF. Now a new falicity, J-PARC, has started operation. Here I will review the progress of hyupernuclear physics in this period. The most important achievements are (1) the establishment of the (pi,K+) reaction spectroscopy at KEK using a large spectrometer called SKS, which includes neutron-rich Lambda hypernuclei, Sigma-nuclear systems, and weak decays of Lambda hypernuclei, and (2) the development of high precision gamma-ray spectroscopy of Lambda hypernuclei using a dedicated Ge detector array, Hyperball, which revealed precise level schemes of most of p-shell Lambda hypernuclei, and (3) the invention of high-resolution (e,e'K+) spectroscopy of hypernuclei at Jefferson Laboratory. I will review each of them, in particular, the gamma-ray spectorscopy, and then describe future prospects at J-PARC.

Speaker: Hirokazu Tamura (Tohoku University)

Slides 1_Hadron2011_Tamura2.ppt

193 In-medium modifications of hadrons

Hadron modifications in hot and/or dense nuclear matter have been predicted by many model calculations. They are commonly discussed in scenarios of chiral symmetry restoration or hadronic many body effects (for recent review see [1]). Experiments with photon, proton and heavy ion beams are used to probe hadron properties in nuclear matter of various forms: from cold nucleus to hot and compressed hadron gas. Most of information have been gathered for light vector mesons (ρ/ω/φ) which, due to their short life time, decay to large extent inside the medium. Decay channels involving dileptons and hadrons have been selected to measure meson line shape and/or nuclear transparency. Significant medium effects have been observed and interpreted in terms of meson broadening. Moreover, measurement of dileptons from heavy ion collisions allows to separate contribution from dense phase and characterize its properties. Review of recent experimental results, focused on low energy domain, will be presented. [1] U. Mosel, S.Leupold, V. Metag Prog.Thoer.Phys.Suppl. 186 (2010) 260

Speaker: Piotr Salabura (Jagiellonian University in Krakow)

Paper hadron_salabura_15102011.zip

Slides hadron_2011_salabura1.ppt

194 Neutrinos: recent results and developments

We will review the current status of experimental neutrino physics. Search for the determination of neutrino masses and oscillation parameters with terrestrial and extra-terrestrial sources will be discussed in the light of the most recent data. The anomalies discovered at accelerator, solar (calibration), reactor neutrino experiments will be presented. The interpretation of these anomalies in terms of the, hypothetical, existence of an fourth sterile neutrino state will be analyzed.

Speaker: Thierry Lasserre (AstroParticule et Cosmologie Paris)

Slides 3_lasserre_hadron2011.pdf

1:00 PM Lunch break

Plenary Session: 10

Convener: Prof. Harry Lipkin (Weizmann Institute of Science)

195 Hadron physics at FAIR

In this presentation the hadron physics programme in preparation at FAIR is presented. After an introduction to FAIR and PANDA the main topics of PANDA in hadron spectroscopy and hadron structure are discussed. In an outlook future topics beyond PANDA are shown.

Speaker: Lars Schmitt (GSI)

Slides lschmitt_fair.pdf

196 The BELLE II project

In the end of June 2010, the Belle project completed its operation after 10 years of experiments and collection of more than 1000 fb-1 of integrated luminosity at the KEKB asymmetric-energy e+e- collider. The energy range of this experiment comprised the area of upsilon meson family. The world highest luminosity of the collider, 2*10^34cm-2s-1, as well as high quality and performance of the Belle detector provided a basis to obtain numerous results in several fields of particle physics. Although the most known Belle achievements concern the CP symmetry violation in the quark sector, very important results were also obtained in the heavy quarkonium spectroscopy, tau lepton decays and two-photon physics. Motivated by the success of the KEKB/Belle experiment, the new advanced project, KEKB II/Belle II was accepted. The KEKB II luminosity will exceed the previous one by about 40 times. In several aspects, Belle II will have considerably higher performance than Belle: • the vertex resolution is improved by the excellent spatial resolution of the two innermost pixel detector layers; • the efficiency of the reconstruction of KS decay to two charged pions with hits in the sili-con strip detector is improved because of a larger volume occupied by this detector; • the new particle identification systems in the barrel and endcap regions extend the very good pion/kaon separation to the kinematic limits of the experiment; • the new electronics of the electromagnetic calorimeter considerably reduce the noise pile up which is especially important for the missing energy studies. This upgrade will open exciting possibilities in a search and study of new physics phenomena in the heavy quarkonia, lepton flavour violation in tau decays as well as in other particle physics fields.

Speaker: Boris Shwartz (Budker Institute of Nuclear Physics)

Paper bsh-cont.zip shwartz-hadron2011.pdf

Slides 2_talk6.ppt

197 Summary Experiment

to be filled

Speaker: Stefano Bianco (INFN Frascati)

Slides 0hadron2011biancoV5.ppt

198 The future of hadrons (theory summary)

to be filled

Speaker: Chris Quigg (FNAL)

Slides 4_CQHadron11.pdf