Speaker
Prof.
Pedro Gonzalez
(University of Valencia)
Description
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).
Primary author
Dr
Ju Jun Xie
(IFIC, University of Valencia)
Co-authors
Dr
Alberto Martinez Torres
(Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan)
Prof.
Eulogio Oset
(IFIC, University of Valencia)
Prof.
Pedro Gonzalez
(University of Valencia)
