Inclusive Charmed-Baryon Decays and Lifetimes

Abstract

We have quantitatively reanalyzed the inclusive charmed-baryon decays. New ingredients are the Voloshin preasymptotic effects in semileptonic decays and the Cabibbo-subleading contributions to both semileptonic and nonleptonic decays. It has been found that the Cabbibo-subleading Voloshin contribution essentially improves the theoretical semileptonic branching ratio of ${\Lambda }_c^{+}$, in agreement with experiment. The semileptonic branching ratios for ${\Xi }_c^{+}$ and ${\Omega }_c^0$ are found to be large, i.e., of the order of 20%. The lifetimes hierarchy is in a good qualitative and even quantitative agreement with experiment except for the ${\Xi }_c^{+}$ lifetime, which is somewhat smaller than the experimental value. Future measurements, especially measurements of the semileptonic branching ratios for ${\Omega }_c^0$, ${\Xi }_c^{+}$ and ${\Xi }_c^0$ should be decisive for the check of this approach.

Comments: 13 pages, Latex, 3 figures included, shortened version, to appear in Z.Phys.C