(No) New physics in B_s mixing and decay

TL;DR

This paper reviews the current status of potential new physics signals in B_s and B_d meson mixing and decay, highlighting recent LHCb results that challenge previous anomalies and emphasizing the need for further independent measurements.

Contribution

It provides an updated analysis of experimental data on B meson mixing, clarifies the tension between different measurements, and discusses the implications for new physics searches.

Findings

LHCb results show no evidence for non-standard phases in B_s mixing.

The D0 like-sign dimuon asymmetry remains difficult to explain.

Independent measurements are crucial to resolve experimental ambiguities.

Abstract

The status of possible new-physics signals in B_s,d-meson mixing and decay is reviewed. In particular, it is emphasized that the recent LHCb results, that find no evidence for a non-standard phase in B_s-barB_s mixing, make a consistent explanation of the D0 data on the like-sign dimuon charge asymmetry notoriously difficult. In order to clarify the inconclusive experimental situation, independent measurements of the semileptonic asymmetries are needed.