Perturbative QCD analysis of $B(B\to Xl\bar{\nu })$, charm yield $<n_c>$ in B decay, and $\tau ({\Lambda }_b)/\tau (B_d)$

We-Fu Chang, Hsiang-nan Li, Hoi-Lai Yu

We apply perturbative QCD factorization theorems to inclusive heavy hadron decays, and obtain simultaneously a low semileptonic branching ratio $B(B\to Xl\bar{\nu })=10.16$, the averag…