基于光锥求和规则和重夸克展开B(s)→a2(1320),K2^*(1430),f2(1270),f′2(1525)跃迁形状因子的计算  

Calculations of B→a(1320),K(1430),f(1270),f′(1525) transition form factors via light cone sum rules and heavy quark expansion

作　　者：左亚兵[1] 陈岩[1] 凌汶 杨威[1] 郝燕南 张卫荣 ZUO Yabing;CHEN Yan;LING Wen;YANG Wei;HAO Yannan;ZHANG Weirong(School of Physics and Electronic Technology,Liaoning Normal University,Dalian 116029,China)

机构地区：[1]辽宁师范大学物理与电子技术学院,辽宁大连116029

出　　处：《辽宁师范大学学报（自然科学版）》2020年第3期317-326,共10页Journal of Liaoning Normal University:Natural Science Edition

基　　金：高等学校博士学科点专项基金资助课题(20132136120003)。

摘　　要：利用光锥求和规则和重夸克展开的方法计算了B(s)到P波2^++轻张量介子a2(1320)、K2^*(1430)、f2(1270)、f′2(1525)跃迁形状因子并利用给出的形状因子对相关半轻衰变的分支比、纵向极化分数等可观测量给出了预言.研究表明,在重夸克极限下,描述企鹅类型形状因子的领头阶波函数与相应描述半轻类型形状因子的领头阶波函数完全一样,从而只有4个半轻类型形状因子是独立的.半轻衰变B(s)→a2(1320)(K2^*(1430),f2(1270),f′2(1525))lvl的分支比在10^-5量级,纵向极化分数大约是0.6~0.7.这些过程将来有可能在超级B工厂和升级后的LHCb实验中观测到.In the present paper,the transition form factors of B(s)to 2^++ light tensor meson a2(1320)、K2^*(1430)、f2(1270)、f′2(1525)are calculated by using the light cone sum rules and heavy quark expansion.With the form factors given here,we predict the branching ratios and longitudinal polarization fractions of relevant semileptonic decays.We found that the leading order wave functions describing penguin type form factors are identical to the corresponding ones describing semileptonic type form factors and therefore only the four semileptonic type form factors are independent.The branching ratios of B(s)→a2(1320)(K2^*(1430),f2(1270),f′2(1525))lvl are at the order of 10^-5 and the longitudinal polarization fractions are about 0.6~0.7.These decays may be observed at the super B factories and LHCb upgraded in the future.

关 键 词：B(s) 轻张量介子 形状因子 分支比 纵向极化分数 

分 类 号：O572.3[理学—粒子物理与原子核物理]