Λ_(b)→Λ_(c) form factors from QCD light-cone sum rules  

作　　者：Yan Miao Hui Deng Ke-Sheng Huang Jing Gao Yue-Long Shen 苗艳;邓慧;黄克胜;高婧;沈月龙(College of Physics and Photoelectric Engineering,Ocean University of China,Qingdao 266100,China;School of Nuclear Science and Technology,and Frontiers Science Center for Rare Isotopes,Lanzhou University,Lanzhou 730000,China;School of Physics,Nankai University,Tianjin 300071,China)

机构地区：[1]College of Physics and Photoelectric Engineering,Ocean University of China,Qingdao 266100,China [2]School of Nuclear Science and Technology,and Frontiers Science Center for Rare Isotopes,Lanzhou University,Lanzhou 730000,China [3]School of Physics,Nankai University,Tianjin 300071,China

出　　处：《Chinese Physics C》2022年第11期154-167,共14页中国物理C（英文版）

基　　金：Supported in part by the National Natural Science Foundation of China(12175218,11975112);the Natural Science Foundation of Shandong province with(ZR2020MA093);supported by the National Natural Science Foundation of China(12147118)。

摘　　要：In this study,we calculate the transition form factors of Λ_(b) decaying into Λ_(c) within the framework of light-cone sum rules with the distribution amplitudes(DAs)of the Λ_(b)-baryon.In the hadronic representation of the correlation function,we isolate both the Λ_(c) and Λ_(c)^(∗) states so that the Λ_(b)→Λ_(c) form factors can be obtained without ambiguity.We investigate the P-type and A-type currents to interpolate light baryons for comparison because the interpolation current for the baryon state is not unique.We also employ three parametrization models for the DAs of Λ_(b) in the numerical calculation.We present the numerical predictions for the Λ_(b)→Λ_(c) form factors and branching fractions,averaged forward-backward asymmetry,averaged final hadron polarization,and averaged lepton polarization of the Λ_(b)→Λ_(c)ℓμ decays,as well as the ratio of the branching ratios RΛ_(c).The predicted RΛ_(c) is consistent with LHCb data.

关 键 词：heavy baryon decays form factors light-cone sum rules 

分 类 号：O572.243[理学—粒子物理与原子核物理]