Non-spectator Contributions To The Lifetime of $\hat{I}{›}_b$

Abstract

In this work, we evaluate the contributions of non-spectator effects to the lifetimes of $\hat{I}{›}_b$ and B-mesons. Based on the well-established models and within a reasonable range of the concerned parameters, the contributions can reduce the lifetime of $\hat{I}{›}_b$ by $7\sim 8$ compared to that of B-mesons which are not significantly affected. This might partly explain the measured ratio $\ddot{I}„(\hat{I}{›}_b)/\ddot{I}„(B^0)=0.79$ \cite{Data}, which has been a long-standing discrepancy between theory and experimental data.