Neutral gauge boson contributions to the dimuon charge asymmetry in B decays

作者：Alok Ashutosh Kumar^*; Baek Seungwon; London David

来源：The Journal of High Energy Physics, 2011, (7): 111.

DOI：10.1007/JHEP07(2011)111

• Beyond Standard Model
• B-Physics
• CP violation

Recently, the Dempty set Collaboration measured the CP-violating like-sign dimuon charge asymmetry in neutral B decays, finding a 3.2 sigma difference from the standard-model (SM) prediction. A non-SMcharge asymmetry a(sl)(s) suggests a new-physics (NP) contribution to B-s-(B) over bar (s) mixing. In this case, in order to explain the measured value of a(sl)(s) within its 1 sigma range, NP must be present in Gamma(s)(12), the absorptive part of the mixing. In this paper, we examine whether such an explanation is possible in models with flavor-changing Z (ZFCNC) or Z' (Z'FCNC) gauge bosons. The models must also reproduce the measured values of the indirect CP asymmetry S-psi phi in B-s -> J/psi phi, and Delta Gamma(s), the B-s-(B) over bar (s) width difference. We find that the ZFCNC model cannot reproduce the present measured values of S-psi phi and a(sl)(s) within their 1 sigma ranges. On the other hand, in the Z'FCNC model, the values of all three observables can be simultaneously reproduced.

• 出版日期2011-7