Spectator interactions and factorization in B -> pi ell nu decay
Abstract
We investigate the factorization of different momentum modes that appear in matrix elements for exclusive B meson decays into light energetic particles for the specific case of B -> pi form factors at large pion recoil. We first integrate out hard modes with virtualities of order m_b^2 (m_b being the heavy quark mass), and then hard-collinear modes with virtualities m_b Lambda (Lambda being the strong interaction scale). The resulting effective theory contains soft and collinear fields with virtualities Lambda^2. We prove a previously conjectured factorization formula for B -> pi form factors in the heavy quark limit to all orders in alpha_s, paying particular attention to `endpoint singularities' that might have appeared in hard spectator interactions.
Cite
@article{arxiv.hep-ph/0308303,
title = {Spectator interactions and factorization in B -> pi ell nu decay},
author = {M. Beneke and Th. Feldmann},
journal= {arXiv preprint arXiv:hep-ph/0308303},
year = {2011}
}
Comments
Contribution to International Europhysics Conference on High Energy Physics, EPS 2003, Aachen (Germany), 3 pages + 1 figure