On the inclusive determination of |V(ub)| from the lepton invariant mass spectrum

Jun, 2000
19 pages
Published in:
  • JHEP 07 (2000) 022
e-Print:
Report number:
  • CLNS-00-1676

Citations per year

200020062012201820240246810
Abstract: (arXiv)
Bauer, Ligeti and Luke have recently proposed a new method for measuring |V_{ub}| in inclusive semileptonic B decays, using a cut on the lepton invariant mass to discriminate against b->c transitions. We investigate the structure of the heavy-quark expansion for this case and show that to all orders the magnitude of the leading perturbative and nonperturbative corrections is controlled by a hadronic scale mu_c=O(m_c) depending on the minimal value of q^2. These corrections can be analyzed using a modified version of the heavy-quark expansion (``hybrid expansion''). We find that the theoretical uncertainty in the extraction of |V_{ub}| is a factor 2.5 larger than previously estimated, which allows for a determination with 10% accuracy.
Note:
  • 19 pages, 8 figures
  • B: semileptonic decay
  • decay: inclusive reaction
  • CKM matrix matrix
  • mass spectrum
  • heavy quark
  • quark: mass
  • correction: higher-order
  • HQET model
  • renormalization group
  • tensor: hadronic