Taming the higher power corrections in semileptonic B decays

摘要

We study the effect of dimension 7 and 8 operators on inclusive semileptonic B decays and the extraction of | V c b | . Using moments of semileptonic B decay spectra and information based on the Lowest-Lying State saturation Approximation (LLSA) we perform a global fit of the non-perturbative parameters of the heavy quark expansion including for the first time the O ( 1 / m b 4 , 5 ) contributions. Higher power corrections appear to have a very small effect on the extraction of | V c b | , independently of the weight we attribute to the LLSA.