B→K1ℓ+ℓ− decays in a family non-universal Z′ model
B→K1ℓ+ℓ− decays in a family non-universal Z′ model
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DOI：
10.1140/epjc/s10052-011-1775-2
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发表时间：
2011-07
期刊：
影响因子：
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通讯作者：
Ying Li;J. Hua;Kwei-Chou Yang
中科院分区：
文献类型：
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作者：
Ying Li;J. Hua;Kwei-Chou Yang
探讨了 B{yields}K{sub 1}(1270,1400)l{sup +}l{sup -}(l=e,{mu},{tau}) 衰变中族非通用 Z' 模型的含义，其中质量本征态 K{sub 1}(1270, 1400) 是 {sup 1} P{sub 1} 和 {sup 的混合3} P{sub 1} 状态具有混合角{theta}。在这项工作中，考虑Z'玻色子并设置混合角{theta}=(-34{+-}13)，我们分析了每种衰变模式的分支比、双轻子不变质谱、归一化前后不对称性和轻子极化不对称性。我们发现 B{yields}K{sub 1}(1270){mu}{sup +}{mu}{sup -} 的所有可观测量都对 Z' 的贡献敏感。而且，B{yields}K{sub 1}(1400){mu}{sup +}{mu}{sup -} 的可观测量具有较强的 {theta} 依赖性；因此，Z'的贡献将被混合角{theta}的不确定性所掩盖。此外，低双轻子质量下B{yields}K{sub 1}(1270){mu}{sup +}{mu}{sup -}的FBA谱中的零交叉位置将随着Z'的贡献向正方向移动。对于 tau 模式，由于相空间较小，Z' 的影响并不显着。这些结果可以在正在运行的LHC-b实验和super-B工厂中进行测试。 （原件）
The implications of the family non-universal Z' model in the B{yields}K{sub 1}(1270,1400)l{sup +}l{sup -}(l=e,{mu},{tau}) decays are explored, where the mass eigenstates K{sub 1}(1270, 1400) are the mixtures of {sup 1} P{sub 1} and {sup 3} P{sub 1} states with the mixing angle {theta}. In this work, considering the Z' boson and setting the mixing angle {theta}=(-34{+-}13) , we analyze the branching ratio, the dilepton invariant mass spectrum, the normalized forward-backward asymmetry and lepton polarization asymmetries of each decay mode. We find that all observables of B{yields}K{sub 1}(1270){mu}{sup +}{mu}{sup -} are sensitive to the Z' contribution. Moreover, the observables of B{yields}K{sub 1}(1400){mu}{sup +}{mu}{sup -} have a relatively strong {theta}-dependence; thus, the Z' contribution will be buried by the uncertainty of the mixing angle {theta}. Furthermore, the zero crossing position in the FBA spectrum of B{yields}K{sub 1}(1270){mu}{sup +}{mu}{sup -} at low dilepton mass will move to the positive direction with Z' contribution. For the tau modes, the effects of Z' are not remarkable due to the small phase space. These results could be tested in the running LHC-b experiment and super-B factory. (orig.)