B介子稀有衰变与荷电PG玻色子企鹅图贡献  

Rare B-Decays and Z^0-Penguin Contributions From the Charged Pseudo-Goldstone Bosons

作　　者：肖振军[1] 张晋宇[1] 吕林霞[1] 鲁公儒[1] 

机构地区：[1]河南师范大学物理系,新乡453002

出　　处：《高能物理与核物理》1999年第7期636-643,共8页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金!19575015

摘　　要：计算了荷电ＰＧ玻色子Ｐ±和Ｐ±８对Ｂ介子稀有衰变过程Ｂ→Ｘｓ，ｄ　和Ｂｓ，ｄ→１＋１－（ｌ＝ｅ，μ，τ）的企鹅图和箱图贡献．计算表明：（ａ）荷电ＰＧ玻色子可以对Ｂ介子稀有衰变分枝比Ｂｒ（Ｂ→Ｘｓ，ｄＶＶ）和Ｂｒ（Ｂｓ，ｄ→１＋１－）给出３～５倍的增强；（ｂ）在大部分参数空间内，色八重态ＰＧ玻色子Ｐ８±起主要作用．In this paper, the one-loop contributions to the rare B-decays B→Xs,v vand Bs,d→1+1(1= e, μ, τ) from the charged pesudo-Goldstone bosons P and P arecalculated. Within the parameter space, we find that: (a) the P± and P8± can providerather large enhancements to the branching ratios of the rare B-decays in question, themaximum increase is about a factor of 3 to Br(B→Xs,d,vv), and a factor of 5 to Br (Bs,d→1+1-); (b) the color-octet pesudo-Goldstone boson P±8 dominates the contributions toall rare B-decays under consideration; (c) no limit on the masses of chargedPesudo-Goldstone bosons can be achieved from the current experimental data, but theforthcoming data may reach the sensitivity to find the signals of new physics beyondthe Standard Model.

关 键 词：B介子稀有衰变 荷电PG玻色子 分枝比 企鹅图 

分 类 号：O572.33[理学—粒子物理与原子核物理]