Taming the higher power corrections in semileptonic B decays

We study the effect of dimension 7 and 8 operators on inclusive semileptonic B decays and the extraction of vertical bar V-cb vertical bar. 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 vertical bar V-cb vertical bar, independently of the weight we attribute to the LLSA. (C) 2016 The Authors. Published by Elsevier B.V.