Forward-backward asymmetries inΛ_(b)→Λl^(+)l^(-)in the Bethe-Salpeter equation approach

作     者：Liang-Liang Liu Su-Jun Cui Jing Xu Xin-Heng Guo 刘亮亮;崔苏君;徐晶;郭新恒

作者机构：College of Physics and information engineeringShanxi Normal UniversityTaiyuan 030031China Department of PhysicsYan-Tai UniversityYantai 264005China College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China 

出 版 物：《Chinese Physics C》 (中国物理C（英文版）)

年 卷 期：2022年第46卷第9期

页      面：94-102页

核心收录：

学科分类：07[理学] 070202[理学-粒子物理与原子核物理] 0702[理学-物理学] 

基　　金：National Natural Science Foundation of China(11905117 11775024) 

主　　题：rare decay Bethe-Salpeter equation heavy flavor physics 

摘      要：Using the Bethe-Salpeter equation(BSE),we investigate the forward-backward asymmetries(AFB)inΛb→Λl^(+)l^(-)(l=e,μ,τ)in the quark-diquark *** approach provides precise form factors that are different from those of quantum chromodynamics(QCD)sum *** calculate the rare decay form factors forΛb→Λl^(+)l^(-)b and investigate the(integrated)forward-backward asymmetries in these decay *** observe the integrated A l FB,ˉA l FB(Λb→Λe^(+)e^(-)=-0.1371,ˉA l FB(Λb→Λμ^(+)μ^(-))=-0.1376,andˉA l FB(Λb→Λτ^(+)τ^(-))=-0.1053;the hadron side asymmetriesˉA h FB(Λb→Λμ^(+)μ^(-))=-0.2315;the lepton-hadron side asymmetriesˉA lh FB(Λb→Λμ^(+)μ^(-))^(-)0.0827;and the longitudinal polarization fractionsˉF L(Λb→Λμ^(+)μ^(-))^(-)0.5681.