%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % template for hadron2011 contribution % % please do not rename this file % % to create document run % % pdflatex hadron2011.tex % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% { % do not remove %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % please define your macros here \makeatletter \@ifundefined{c@affiliation}% {\newcounter{affiliation}}{}% \makeatother \newcommand{\affiliation}[2][]{\setcounter{affiliation}{#2}% \ensuremath{{^{\alph{affiliation}}}\text{#1}}} % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % define title, author, and address % contribution[short title]{title}{author first name}{author last name}{author address}{author email}{collaboration} % the short title will appear in the page headers and the TOC of the book of proceedings % the last two arguments may be left empty \contribution[Weak decays of doubly charmed baryons] % short title (optional) {Weak decays of doubly charmed baryons} % title {Eliecer}{Hern\'andez} % presenter of the talk/poster {\affiliation[ Departamento de F\'{\i}sica Fundamental e IUFFyM]{1}\\ Universidad de Salamanca, E-37008 Salamanca, SPAIN \affiliation[ Instituto de F\'\i sica Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia]{2}\\ Institutos de Investigaci\'on de Paterna, Aptd. 22085, E-46071 Valencia, SPAIN } {gajatee@usal.es} {\!\!$^,\affiliation{1}$, Conrado Albertus\affiliation{1}, and Juan Nieves\affiliation{2}} % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % abstract \abstract{% Within a nonrelativistic quark model, we evaluate exclusive semileptonic decays of ground-state spin-1/2 doubly heavy charmed baryons driven by a quark $c\to s,d$ transition. } % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % main text % for short contributions sections are optional We shall only present final results for the decay widths. For the interested reader, Ref.~\cite{Albertus:2011xz} gives a full account of our work. In particular, a discussion on heavy quark spin symmetry constraints on form factors and the level to which those constraints are satisfied for the actual $c$-quark mass can be found there. The quantum numbers of the baryons involved in our study are shown in Table~\ref{tab:baryons}. Quark model masses have been taken from our previous works in Refs.~\cite{Albertus:2003sx,Albertus:2009ww}. Experimental masses are the ones given by the PDG\cite{pdg10} and in the table we quote the average over the different charge states. With the exception of the $\Xi_{cc}$, the agreement is fairly good. In the calculation we use experimental masses. For the $\Omega_{cc}$, and in the absence of experimental information, we take our model prediction of $M_{\Omega_{cc}}=3712\,$MeV. In Table~\ref{tab:dw} we give our results. To the best of our knowledge there are just a few other calculations of exclusive semileptonic decays of ground-state spin-1/2 doubly charmed baryons. Those are also shown in Table~\ref{tab:dw} for comparison. In Ref.~\cite{Faessler:2001mr} only the $\Xi_{cc}\to \Xi'_c e^+\nu_e$ decay was evaluated using the relativistic three-quark model. In Ref.~\cite{Kiselev:2001fw}, the authors use heavy quark effective theory and non-relativistic QCD sum rules to evaluate both the lifetime of the $\Xi_{cc}$ baryon and the branching ratio for the combined decay $\Xi_{cc}\to\Xi_c e^+\nu_e+\Xi'_c e^+\nu_e+\Xi_c^*e^+\nu_e$ from which we have obtained the semileptonic decay widths shown in the table. We find a fair agreement of our predictions with both calculations. We also give results for exclusive semileptonic $c\to s $ decays of the $\Omega_{cc}^+$ baryon and for sub dominant $c\to d$ decays of both the $\Xi_{cc}^{++},\,\Xi_{cc}^+$ and $\Omega_{cc}$ baryons. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % the recommended way to include a LaTeX table \begin{table}[tb] \small \begin{center} \begin{tabular}{ccccccc} Baryon &~~~~$J^\pi$~~~~&~~~~$S^\pi$~~~~& Quark content &\multicolumn{2}{c}{Mass\ [MeV]}\\\cline{5-6} & & & & Quark model & Experiment \\ & & & & \cite{Albertus:2003sx,Albertus:2009ww} & \cite{pdg10} \\ \hline $\Xi_{cc}$ &$\frac12^+$& $1^+$&$ccn$&3613&3518.9 \\ $\Omega_{cc}$ &$\frac12^+$& $1^+$&$ccs$&3712&--\\\hline $\Lambda_c$ &$\frac12^+$& $0^+$&$udc$&2295&2286.5 \\ $\Sigma_c$ &$\frac12^+$& $1^+$&$nnc$&2469&2453.6 \\ $\Sigma^*_c$ &$\frac32^+$& $1^+$&$nnc$&2548&2518.0 \\ $\Xi_c$ &$\frac12^+$&$0^+$&$nsc$&2474&2469.3 \\ $\Xi'_c$ &$\frac12^+$&$1^+$&$nsc$&2578&2576.8 \\ $\Xi^*_c$ &$\frac32^+$&$1^+$&$nsc$&2655&2645.9 \\ $\Omega_c$ &$\frac12^+$& $1^+$&$ssc$&2681&2695.2 \\ $\Omega^*_c$ &$\frac32^+$& $1^+$&$ssc$&2755&2765.9 \\ \end{tabular} \caption{\small Quantum numbers of the baryons involved in this study. $J^\pi$ is the spin-parity of the baryon, while $S^\pi$ is the spin-parity of the two heavy or the two light quark subsystem. $n$ denotes a $u$ or $d$ quark. } \label{tab:baryons} \end{center} \end{table}% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \begin{table}[h!!!] \small \begin{center} \begin{tabular}{lcccc} &&This work&\cite{Faessler:2001mr}&\cite{Kiselev:2001fw}\\\hline $\Gamma(\Xi_{cc}^{++}\to\Xi^+_ce^+\nu_e)$&$(c\to s)$&$8.75\times 10^{-2}$\\ $\Gamma(\Xi_{cc}^{+\hspace{.18cm}}\to\Xi^0_ce^+\nu_e)$&$(c\to s)$&$8.68\times 10^{-2}$\\ $\Gamma(\Xi_{cc}^{++}\to\Xi^{\prime+}_ce^+\nu_e)$&$(c\to s)$&0.146&$0.208\div 0.258$\\ $\Gamma(\Xi_{cc}^{+\hspace{.18cm}}\to\Xi^{\prime\,0}_ce^+\nu_e)$&$(c\to s)$&0.145&$0.208\div 0.258$\\ $\Gamma(\Xi_{cc}^{++}\to\Xi^{*\,+}_ce^+\nu_e)$&$(c\to s)$&$3.20\times 10^{-2}$\\ $\Gamma(\Xi_{cc}^{+\hspace{.18cm}}\to\Xi^{*\,0}_ce^+\nu_e)$&$(c\to s)$&$3.20\times 10^{-2}$\\ $\Gamma(\Xi_{cc}^{++}\to(\Xi^{+}_c +\Xi^{\prime+}_c+\Xi^{*\,+})e^+\nu_e)$& $(c\to s)$&0.266&&$0.37\pm0.04^{(*)}$\\ $\Gamma(\Xi_{cc}^{+\hspace{.18cm}}\to(\Xi^{0}_c+\Xi^{\prime\,0}_c+\Xi^{*\,0}_c)e^+\nu_e)$&$(c\to s)$&0.264&&$0.47\pm0.15^{(*)}$\\ $\Gamma(\Xi_{cc}^{++}\to\Lambda^+_ce^+\nu_e)$\hspace*{.5cm}&$(c\to d)$&$4.86\times 10^{-3}$\\ $\Gamma(\Xi_{cc}^{++}\to\Sigma^+_ce^+\nu_e)$&$(c\to d)$&$7.94\times 10^{-3}$\\ $\Gamma(\Xi_{cc}^{+\hspace{.18cm} }\to\Sigma^0_ce^+\nu_e)$&$(c\to d)$&$1.58\times 10^{-2}$\\ $\Gamma(\Xi_{cc}^{++}\to\Sigma^{*\,+}_ce^+\nu_e)$&$(c\to d)$&$1.77\times 10^{-3}$\\ $\Gamma(\Xi_{cc}^{+\hspace{.18cm}}\to\Sigma^{*\,0}_ce^+\nu_e)$&$(c\to d)$&$3.54\times 10^{-3}$\\ \hline $\Gamma(\Omega_{cc}^{+\hspace{.18cm}}\to\Omega^{0}_ce^+\nu_e)$&$(c\to s)$&0.282\\ $\Gamma(\Omega_{cc}^{+\hspace{.18cm}}\to\Omega^{*\,0}_ce^+\nu_e)$&$(c\to s)$&$5.77\times 10^{-2}$\\ $\Gamma(\Omega_{cc}^{+\hspace{.18cm}}\to\Xi^{0}_ce^+\nu_e)$&$(c\to d)$&$4.11\times 10^{-3}$\\ $\Gamma(\Omega_{cc}^{+\hspace{.18cm}}\to\Xi^{\prime\,0}_ce^+\nu_e)$&$(c\to d)$&$7.44\times 10^{-3}$\\ $\Gamma(\Omega_{cc}^{+\hspace{.18cm}}\to\Xi^{*\,0}_ce^+\nu_e)$&$(c\to d)$&$1.72\times 10^{-3}$ \end{tabular} \end{center} \caption{\small Decay widths in units of ${\rm ps}^{-1}$. We use $|V_{cs}|=0.97345$ and $|V_{cd}|=0.2252$ taken from Ref.~\cite{pdg10}. Results with an ${(\ast)}$, our estimates from the total decay widths and branching ratios in~\cite{Kiselev:2001fw}. Similar results are obtained for $\mu^+\nu_\mu$ leptons in the final state.} \label{tab:dw} \end{table} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % acknowledgements (optional) \acknowledgements{ Research supported by contracts FIS2006-03438, FIS2008-01143/FIS, FPA2010-21750-C02-02, CSD2007-00042, PROMETEO/20090090 and by the EU HadronPhysics2 project, grant agreement no. 227431. C. A. thanks a Juan de la Cierva contract from the Spanish Ministerio de Educaci\'on y Ciencia. } %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % bibliographic items can be constructed using the LaTeX format in SPIRES % see http://www.slac.stanford.edu/spires/hep/latex.html % SPIRES will also supply the CITATION line information; please include it \begin{thebibliography}{99} %\cite{Albertus:2011xz} \bibitem{Albertus:2011xz} C.~Albertus, E.~Hernandez and J.~Nieves, %``Exclusive $c\to s,d$ semileptonic decays of ground-state spin-1/2 doubly %charmed baryons,'' arXiv:1108.1296 [hep-ph]. %%CITATION = ARXIV:1108.1296;%% %\cite{Albertus:2003sx} \bibitem{Albertus:2003sx} C.~Albertus, J.~E.~Amaro, E.~Hernandez and J.~Nieves, %``Charmed and bottom baryons: A Variational approach based on heavy quark %symmetry,'' Nucl.\ Phys.\ A {\bf 740}, 333 (2004). %[arXiv:nucl-th/0311100]. %%CITATION = NUPHA,A740,333;%% % %\cite{Albertus:2009ww} \bibitem{Albertus:2009ww} C.~Albertus, E.~Hernandez and J.~Nieves, %``Hyperfine mixing in b ---> c semileptonic decay of doubly heavy baryons,'' Phys.\ Lett.\ B {\bf 683}, 21 (2010). % [arXiv:0911.0889 [hep-ph]]. %%CITATION = PHLTA,B683,21;%% % \bibitem{pdg10} K. Nakamura et al. (Particle Data Group), J. Phys. G 37, 075021 (2010). %%\cite{Faessler:2001mr} \bibitem{Faessler:2001mr} A.~Faessler, T.~Gutsche, M.~A.~Ivanov, J.~G.~Korner and V.~E.~Lyubovitskij, %``Semileptonic decays of double heavy baryons,'' Phys.\ Lett.\ B {\bf 518}, 55 (2001). % [arXiv:hep-ph/0107205]. %%CITATION = PHLTA,B518,55;%% %\cite{Kiselev:2001fw} \bibitem{Kiselev:2001fw} V.~V.~Kiselev and A.~K.~Likhoded, %``Baryons with two heavy quarks,'' Phys.\ Usp.\ {\bf 45}, 455 (2002) [Usp.\ Fiz.\ Nauk {\bf 172}, 497 (2002)] [arXiv:hep-ph/0103169]. %%CITATION = UFNAA,172,497;%% See also A.I. Onishchenko, hep-ph/9912425; A.I. Onishchenko, hep-ph/0006271; A.I. Onishchenko, hep-ph/0006295. \end{thebibliography} % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% } % do not remove %%% Local Variables: %%% mode: latex %%% TeX-master: "../hadron2011.tex" %%% End: