Probing the sources of CP violation via B -> K^* l^+ l^- decay

TL;DR

This paper investigates how CP violation and lepton polarization asymmetries in B -> K^* l^+ l^- decays can reveal new CP-odd phases beyond the Standard Model, offering potential signals of new physics.

Contribution

It analyzes the sensitivity of CP and lepton polarization asymmetries to new CP-odd phases in Wilson coefficients within an extended Standard Model framework.

Findings

CP asymmetry is sensitive to phase in Wilson coefficient C_7

Normal lepton polarization asymmetry is sensitive to phase in C_(10)

Correlation between asymmetries can indicate new CP violation sources

Abstract

The B -> K^* l^+ l^- (l = mu, tau) is analyzed in a minimally extended Standard Model in which the Wilson coefficients have new CP-odd phases. The sensitivity of the CP asymmetry and lepton polarization asymmetries to the new phases is discussed. It is found that the CP asymmetry is sensitive to the new phase in the Wilson coefficient C_7 whereas the normal lepton polarization asymmetry is sensitive to the phase in the Wilson coefficient C_(10). Additionally, the correlation between the CP and normal lepton polarization asymmetries is studied. A simultaneous measurement of these two asymmetries can be useful in search for the existence of the new sources of CP violation beyond the Standard Model.