Charmed Baryons with $J=3/2$

Abstract

The width of a recently discovered excited charmed-strange baryon, a candidate for a state ${\Xi }_c^{\ast }$ with spin 3/2, is calculated. In the absence of configuration mixing between the ground-state (spin-1/2) charmed-strange baryon ${\Xi }_c^{(a)}$ and the spin-1/2 state ${\Xi }_c^{(s)}$ lying about 95 MeV above it, one finds $\tilde{\Gamma }({\Xi }_c^{\ast }\to {\Xi }_c^{(a)}\pi )=(3/4)\tilde{\Gamma }({\Xi }^{\ast }\to \Xi \pi )$ and $\tilde{\Gamma }({\Xi }_c^{\ast }\to {\Xi }_c^{(s)}\pi )=(1/4)\tilde{\Gamma }({\Xi }^{\ast }\to \Xi \pi )$, where the tilde denotes the partial width with kinematic factors removed. Assuming a kinematic factor for P-wave decay of $p_{\mathrm{cm}}^3$, one predicts $\Gamma ({\Xi }_c^{\ast }\to {\Xi }_c^{(a)}\pi )=2.3$ MeV, while the ${\Xi }_c^{\ast }\to {\Xi }_c^{(s)}\pi$ channel is closed. Some suggestions are given for detecting the ${\Sigma }_c^{\ast }$, the spin-3/2 charmed nonstrange baryon, and the ${\Omega }_c^{\ast }$, the spin-3/2 charmed doubly-strange baryon.

Comments: 11 pages, latex, 2 uuencoded figures sent separately