Work

Factorization formula connecting the shape functions of heavy meson in QCD and heavy quark effective theory

Year: 2025

Type: article

Abstract: The shape function of the B -meson defined in heavy quark effective theory plays a crucial role in the analysis of inclusive B decays, and constitutes one of the dominant uncertainties in the determination of Cabbibo-Kobayashi-Maskawa matrix element | V u b | . On the other hand, the conventional heavy meson shape function defined in QCD is also phenomenologically important and includes short-distance physics at energy scales of the heavy quark mass. In this work, we derive a factorization formula relating these two kinds of shape functions, which can be invoked to fully disentangle the effects from disparate scales m b and Λ QCD , particularly to facilitate the resummation of logarithms ln m b / Λ QCD . In addition, this factorization constitutes an essential component of the recently developed two-step factorization scheme, enabling lattice QCD calculations of light cone quantities of heavy meson. The results presented here pave the way for first-principles nonperturbative predictions of shape function in the near future.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/1547-t91t

Authors: Wei Wang, Ji Xu, Qi-An Zhang, Shuai Zhao

Institutions: Shanghai Jiao Tong University, Lanzhou University, Beihang University, Tianjin University

Language: English

Topic: Quantum Chromodynamics and Particle Interactions

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funder: National Natural Science Foundation of China

Awards: G2585964420, G5670925003, G5687198492, G7504224031