Lifetimes of b-flavoured hadrons

Abstract

I discuss the heavy quark expansion for the inclusive widths of heavy-light hadrons, which predicts quite well the experimental ratios of B_q meson lifetimes. As for ${\Lambda }_b$, current determinations of $\mathcal{O}(m_b^{-3})$ contribution to $\tau ({\Lambda }_b)$ do not allow to explain the small measured value of $\tau ({\Lambda }_b)/\tau (B_d)$. As a final topic, I discuss the implications of the measurement of the B_c lifetime.

Comments: LaTex, 4 pages, 1 figure. Talk given at the "U.K. Phenomenology Workshop on Heavy Flavours and CP violation" Durham, 17-22 Sep. 2000 (Mixing and Lifetimes Working Group)