BSM models facing the recent LHCb data: A first look

TL;DR

This paper assesses how recent LHCb data impacts various BSM models' predictions for flavour observables, highlighting which models are favored or challenged by the new measurements.

Contribution

It provides the first semi-quantitative analysis of the effects of recent LHCb data on BSM models' flavour predictions, including updated lattice inputs.

Findings

LHCb data constrains BSM models' ability to predict large CP asymmetries.

Some BSM models are now less favored due to new data.

Standard models like CMFV face difficulties explaining all observables.

Abstract

During last decade a number of detailed analyses of flavour observables and of their correlations within more than a dozen specific BSM models have been performed at the TUM. One of the goals of these analyses was to investigate which model is capable of obtaining large mixing induced CP asymmetry in the B_s system, S_{psi phi}, and to find out what this would imply for other flavour observables. In this context also the rare decays B_{s,d}->mu^+ mu^- have been considered. In some models their branching ratios can be enhanced by orders of magnitude above the SM expectations. The recent data on S_{psi phi} and B_{s,d}-> mu^+ mu^- from the LHCb put an end to these very optimistic hopes modifying significantly the allowed patterns of deviations from SM predictions for flavour observables in concrete BSM models. We make a first semi-quantitative assessment of the most important modifications in the predictions of the BSM models in question including also recently analyzed models and taking into account the most recent lattice input. For some BSM models the LHCb data turned out to be a relief. On the other hand the SM, models with CMFV and MFV models without flavour blind phases appear to have significant difficulties in describing all Delta F=2 observables in B_{s,d} and K^0 meson systems simultaneously. We propose to regard the stringent CMFV relations between various observables as standard candels of flavour physics. The pattern of deviations from these relations may help in identifying the correct NP scenario.