Implications of lepton flavor universality violations in B decays

TL;DR

This paper investigates the anomalies in B meson decays suggesting lepton flavor universality violation, exploring new physics models and their implications for future experiments and collider searches.

Contribution

It provides a comprehensive analysis of potential new physics explanations for the B decay anomalies, including flavor violation scenarios and specific model examples.

Findings

Minimal flavor violating models are disfavored but not excluded.

Right-right vector and right-left scalar currents are viable explanations.

Implications for LHC searches and future B factory measurements are discussed.

Abstract

Present measurements of b->c tau nu and b->u tau nu transitions differ from the standard model predictions of lepton flavor universality by almost 4sigma. We examine new physics interpretations of this anomaly. An effective field theory analysis shows that minimal flavor violating models are not preferred as an explanation, but are also not yet excluded. Allowing for general flavor violation, right-right vector and right-left scalar quark currents are identified as viable candidates. We discuss explicit examples of two Higgs doublet models, leptoquarks as well as quark and lepton compositeness. Finally, implications for LHC searches and future measurements at the (super)B- factories are presented.