1210.6992 (C. M. Bouchard et al.)

Form factors for B and B_s semileptonic decays with NRQCD/HISQ quarks    [PDF]

C. M. Bouchard, G. Peter Lepage, Chris J. Monahan, Heechang Na, Junko Shigemitsu

We discuss preliminaries of a calculation of the form factors for the semileptonic decays B -> pi lv, B_s -> K lv, and B -> K ll. We simulate with NRQCD heavy and HISQ light valence quarks on the MILC 2+1 dynamical asqtad configurations. The form factors are calculated over a range of momentum transfer to allow determination of their shape and the extraction of |V_ub|. Additionally, we are calculating ratios of these form factors to those for the unphysical decay B_s -> eta_s. We are studying the possibility of combining these precisely determined ratios with future calculations of B_s ->eta_s using HISQ b-quarks to generate form factors with significantly reduced errors.

View original: http://arxiv.org/abs/1210.6992