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arXiv · 1010.1333

Neutral Gauge Boson Contributions to the Dimuon Charge Asymmetry in B Decays

Ashutosh Kumar Alok·Seungwon Baek·David London
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Abstract

Recently, the D0 Collaboration measured the CP-violating like-sign dimuon charge asymmetry in neutral B decays, finding a 3.2sigma difference from the standard-model (SM) prediction. A non-SM charge asymmetry a_sl^s suggests a new-physics (NP) contribution to Bs-Bsbar mixing. In this case, in order to explain the measured value of a_sl^s within its 1sigma range, NP must be present in Gamma_12^s, 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 Bs -> J/psi phi, and Delta Gamma_s, the Bs-Bsbar width difference. We find that the ZFCNC model cannot reproduce the present measured values of S_psi-phi and a_sl^s within their 1sigma ranges. On the other hand, in the Z'FCNC model, the values of all three observables can be simultaneously reproduced.

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Ashutosh Kumar Alok, Seungwon Baek, David London. 2010-10-29. Neutral Gauge Boson Contributions to the Dimuon Charge Asymmetry in B Decays. https://doi.org/10.1007/jhep07(2011)111

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