Journal of High Energy Physics

, 2010:82 | Cite as

Family non-universal Z′ effects on \( {\bar B_q} - {B_q} \) mixing, BX s μ + μ and B s μ + μ decays



Motivated by the large discrepancy of CP-violating phase in \( {\bar B_s} - {B_s} \) mixing between the experimental data and the Standard Model prediction, we pursue possible solutions within a family non-universal Z′ model. Within such a specific model, we find that both the \( {\bar B_s} - {B_s} \) mixing anomaly and the well-known “πK puzzle” could be moderated simultaneously with a nontrivial new weak phase, ϕ s L ∼ −72° (S1) or −82° (S2). With the stringently constrained Z′ coupling B sb L , we then study the Z′ effects on the rare BX s μ + μ and B s μ + μ decays, which are also induced by the same bs transition. The observables of BX s μ + μ , at both high and low q 2 regions, are found to be able to put strong constraints on the μμZ′ coupling, B μμ L,R ∼ 10−2. It is also shown that the combined constraints from \( {\bar B_s} - {B_s} \) mixing, BπK and BX s μ + μ do not allow a large Z′ contribution to the pure leptonic B s μ + μ decay.


Rare Decays Beyond Standard Model B-Physics 


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Copyright information

© SISSA, Trieste, Italy 2010

Authors and Affiliations

  1. 1.Institute of Particle PhysicsHuazhong Normal UniversityWuhan, HubeiP. R. China
  2. 2.Department of PhysicsHenan Normal UniversityXinxiang, HenanP.R. China
  3. 3.Institut für Theoretische Physik ERWTH Aachen UniversityAachenGermany
  4. 4.Key Laboratory of Quark & Lepton Physics, Ministry of EducationHuazhong Normal UniversityWuhan, HubeiP. R. China

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