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 $Λ_c^{+}$, in agreement with experiment. The semileptonic branching ratios for $Ξ_c^{+}$ and $Ω_c^{0}$ 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 $Ξ_c^{+}$ lifetime, which is somewhat smaller than the experimental value. Future measurements, especially measurements of the semileptonic branching ratios for $Ω_c^{0}$, $Ξ_c^{+}$ and $Ξ_c^{0}$ should be decisive for the check of this approach.

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