2012/01/31 by Hsiang-nan Li, Yue-Long Shen, Yu-Ming Wang · 115 citations
Mathematics · Physics and Astronomy · #Algorithm #B meson #Factorization #High-Energy Particle Collisions Research #Mathematical physics #Mathematics #Meson #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quark #Renormalization #Renormalization group #Weierstrass factorization theorem #hep-ex #hep-lat #hep-ph
paper · pdf · doi:10.1103/physrevd.85.074004
published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 85(7) (American Physical Society) · 16 pages, 13 figures, version to appear in Phys. Rev. D
arxiv created 2012/03/06 · openalex publication_date 2012/04/03 · arxiv updated 2013/05/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We calculate next-to-leading-order (NLO) corrections to the B\ensuremath→\ensuremathπ transition form factors at leading twist in the kT factorization theorem. Light partons off shell by kT2 are considered in the quark diagrams, in the effective diagrams for the B-meson wave function defined with the effective heavy-quark field, and in the effective diagrams for the pion wave function. It is explicitly demonstrated that the infrared logarithms lnkT2 cancel between the above sets of diagrams, as deriving the kT-dependent NLO hard kernel from their difference. The infrared finiteness of the hard kernel confirms the application of the kT factorization theorem to B-meson semileptonic decays. The NLO pion wave function is identical to those constructed from the pion transition and electromagnetic form factors, consistent with its universality. Choosing the renormalization and factorization scales lower than the B-meson mass, the NLO corrections are under control: they amount only up to 30% of the form factors at large recoil of the pion, when varying models for the meson wave functions.