Theory of Beauty Lifetimes

Abstract

A critical review of the theoretical understanding of the lifetimes of beauty hadrons is given. A model-independent analysis using the heavy-quark expansion allows for a description of the lifetime ratios tau(B-)/tau(B0) and tau(Lambda_b)/tau(B0) in a small region of parameter space. It is demonstrated that the lifetime ratio tau(B-)/tau(B0) cannot be used to extract the decay constant of the B meson. Implications for the semileptonic branching ratio and charm yield in B decays are pointed out.

13 pages, 4 figures embedded. Invited talk presented at the Second International Conference on B Physics and CP Violation, Honolulu, Hawaii, 24-27 March 1997