Cargando…

|V$_{cb}$| from inclusive semileptonic B decays

We determine |V_{cb}| from inclusive semileptonic B decays including resummation of supposedly large perturbative corrections, which originate 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 renorma...

Descripción completa

Detalles Bibliográficos
Autor principal: Ball, Patricia
Lenguaje:eng
Publicado: 1995
Materias:
Acceso en línea:http://cds.cern.ch/record/283346
Descripción
Sumario:We determine |V_{cb}| from inclusive semileptonic B decays including resummation of supposedly large perturbative corrections, which originate 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 |V_{cb}| from inclusive decays is still possible if one uses a short-distance b quark mass. We find that using the \overline{\rm MS} running mass significantly reduces the perturbative coefficients already in low orders. For a semileptonic branching ratio of 10.9\% we obtain |V_{cb}|(\tau_B/1.50\,{\rm ps})^{1/2}=0.041\pm 0.002\pm 0.002. This work was done in collaboration with M. Beneke and V.M.\ Braun.