Analysis of Bs→φμ+μ- decay within supersymmetry

Motivated by the rst measurement on B(B_s→φμ⁺μ^-) by the CDF Collaboration, we study the supersymmetric e ects in semi-leptonic B_s→φμ⁺μ^- decay. In our evaluations, we analyze the dependences of the dimuon invariant mass spectrum and the forward-backward asymmetry on relevant supersymmetric couplings in the MSSM with and without R-parity. The analyses show that the new experimental upper limits of B(B_s→φμ⁺μ^-)from the LHCb Collaboration could further improve the bounds on sneutrino exchange couplings and (δ_LL^u)₂₃ as well as (δ_LL,RR^u)₂₃ mass insertion couplings. In addition, within the allowed ranges of relevant couplings under the constraints from B(B_s→φμ⁺μ^-), B(B→K^(*)μ⁺μ^-) and (B_s→φμ⁺μ^-), the dimuon forward-backward asymmetry and the di erential dimuon forward-backward asymmetry of B_s→φμ⁺μ^-are highly sensitive to the squark exchange contribution and the (δ_LL^u)₂₃ mass insertion contribution. The results obtained in this work will be very useful in searching for supersymmetric signals at the LHC.     

QCD因子化在湮没衰变B0s,d→J/ψ γ中的应用

在QCD因子化框架下,对可能的辐射湮灭衰变B0s,d→J/ψ γ进行研究.在标准模型中,相对于简单因子化下领头阶的分支比,as阶非因子化辐射修正对分支比有显著的量级上的改变,这些衰变可用来检验因子化方法.在理论上,B介子稀有辐射衰变对超出标准模型的新物理特别敏感.作为一个例子,我们考虑右手带电流对标准模型中左手流可能的混合效应,这个混合对衰变分支比有显著的影响.     

Supersymmetric contributions to B_s → K~-π~＋ decay

Recently,the CDF Collaboration has measured the branching fraction and time-integrated direct CP asymmetry of Bs → K-π＋ decay.The branching ratio is lower than the previous predictions based on QCD factorization.The experimental results favor a large CP asymmetry in Bs → K-π＋ decay while the standard model prediction is very small.We compute the supersymmetry contributions to Bs → K-π＋ decay using the mass insertion method,and find that the LR and RL mass insertions could suppress this branching ratio and increase this direct CP asymmetry well in line with the experimental data.     

探测B_s~0-_s~0混合中的R宇称破缺超对称效应(英文)

最近由CDF合作组和DΦ合作组测量的Bs质量差ΔMs粗略地与标准模型预测值一致,因此这些测量将对限制超出标准模型的新物理信号提供一个机会．考虑Bs0-s0混合中的R宇称破缺超对称效应,并用最近ΔMs的实验结果去限制树图的R宇称破缺耦合．然后,通过从ΔMs实验限制得到R宇称破缺耦合的参数空间,显示在Bs宽度差ΔΓs中的R宇称破缺超对称效应．     

探测B0s—B0s混合中的R宇称破缺超对称效应

最近由CDF合作组和DO合作组测量的B_s质量差ΔM_s粗略地与标准模型预测值一致, 因此这些测量将对限制超出标准模型的新物理信号提供一个机会. 考虑B0s—B0s混合中的R宇称破缺超对称效应, 并用最近ΔM_s的实验结果去限制树图的R宇称破缺耦合. 然后, 通过从ΔM_s实验限制得到R宇称破缺耦合的参数空间, 显示在B_s宽度差ΔΓ_s中的R宇称破缺超对称效应.