1995/03/31 by Patricia Ball, P. Ball, Μ. Beneke +2 · 6 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.52.3929
published as Phys.Rev.D52:3929-3948,1995 · 37 pages + 4 figures, final version accepted for publication in Phys. Rev. D
arxiv created 1995/07/27 · openalex publication_date 1995/10/01 · arxiv updated 2010/11/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present a determination of \ensuremath\VertVcb\ensuremath\Vert from semileptonic B decays that includes resummation of supposedly large perturbative corrections, originating from the running of the strong coupling. We argue that the low value of the BLM scale found previously for inclusive decays is a manifestation of the renormalon divergence of the perturbative series starting already in third order. A reliable determination of \ensuremath\VertVcb\ensuremath\Vert from inclusive decays is possible if one either uses a short-distance b quark mass or eliminates all unphysical mass parameters in terms of measured observables, such that all infrared contributions of order 1/mb cancel explicitly. We find that using the MS\ifmmode\else\textasciimacron\fi running mass significantly reduces the perturbative coefficients already in low orders. For a semileptonic branching ratio of 10.9% we obtain \ensuremath\VertVcb\ensuremath\Vert(\mathrm\ensuremathτB/1.50 ps)1/2=0.041\ifmmode±\else\textpm\fi0.002 from inclusive decays, in good agreement with the value extracted from exclusive decays.