Discrepancy in the Unitarity Triangle fit from b s transitions

Abstract

We combine all the available experimental information on Bs mixing, including the recent tagged analyses of Bs→J/Ψφ by the CDF and DO/ collaborations. We find that the phase of the Bs mixing amplitude deviates about 2.5σ from the Standard Model prediction. While no single Tevatron experiment has a significant evidence yet, all the constraints show a remarkable agreement with the combined result. This is an interesting hint of physics beyond the Standard Model. In particular, this result disfavours New Physics models with Minimal Flavour Violation with the same significance.