Tau _{B_{s}}/tau _{B_{d}} and Delta Gamma _{s} confront new physics in brightarrow stau tau

Abstract

Several new physics scenarios that address anomalies in B-physics predict an enhancement of b rightarrow s tau tau with respect to its Standard Model prediction. Such scenarios necessarily imply modifications of the lifetime ratio tau _{B_{s}}/tau _{B_{d}} and the lifetime difference Delta Gamma _{s}. In this work, we explore indirect bounds provided by these observables over new physics scenarios. We also estimate future projections, showing that future experimental and theoretical improvements on both tau _{B_{s}}/tau _{B_{d}} and Delta Gamma _{s} have the potential to provide bounds competitive with those directly extracted from brightarrow s tau tau transitions. After performing a model-independent analysis, we apply our results to the particular case of leptoquark mediators proposed to address the R_{D^{(*)}} anomalies.