First evidence of new physics in b ↔ s transitions

Abstract

We combine all the available experimental information on Bs mixing, including the very recent tagged analyses of Bs → J/Ψϕ by the CDF and DØ collaborations. We find that the phase of the Bs mixing amplitude deviates more than 3σ from the Standard Model prediction. While no single measurement has a 3σ significance yet, all the constraints show a remarkable agreement with the combined result. This is a first evidence of physics beyond the Standard Model. This result disfavours New Physics models with Minimal Flavour Violation with the same significance.