B --> K* mu+ mu-: SM and Beyond

TL;DR

This paper analyzes the decay B --> K* mu+ mu- as a sensitive probe for testing the Standard Model and exploring New Physics effects through angular observables and form factors.

Contribution

It provides a comprehensive study of angular observables in B --> K* mu+ mu- decay, incorporating full form factors and QCD corrections, and evaluates their sensitivity to New Physics models.

Findings

Certain observables show small dependence on hadronic uncertainties.

Some observables are highly sensitive to New Physics effects.

The analysis identifies promising observables for future experimental tests.

Abstract

The rare decay B --> K* mu+ mu- is considered to be a golden channel for LHCb, as the polarization of the K* allows a precise angular reconstruction resulting in many observables that offer new important tests of the Standard Model and its extensions. These angular observables can be expressed in terms of CP-conserving and CP-violating quantities which we study in terms of the full form factors calculated from QCD sum rules on the light-cone, including QCD factorization corrections. We investigate all observables in the context of the Standard Model and various New Physics models, in particular the Littlest Higgs model with T-parity and various MSSM scenarios, identifying those observables with small to moderate dependence on hadronic quantities and large impact of New Physics.