CP Violating Asymmetry in Stop Decay into Bottom and Chargino

TL;DR

This paper calculates the CP violating decay rate asymmetry in stop decays within the MSSM, considering full one-loop corrections and parameter dependencies, with implications for LHC measurements.

Contribution

It provides the first detailed numerical analysis of CP asymmetry in stop decays at full one-loop level in the MSSM with complex parameters.

Findings

Asymmetries of several percent are predicted.

Dependence on complex phases and parameters is analyzed.

Feasibility of measuring the asymmetry at the LHC is discussed.

Abstract

In the MSSM with complex parameters, loop corrections to the decay of a stop into a bottom quark and a chargino can lead to a CP violating decay rate asymmetry. We calculate this asymmetry at full one-loop level and perform a detailed numerical study, analyzing the dependence on the parameters and complex phases involved. In addition, we take the Yukawa couplings of the top and bottom quark running. We account for the constraints on the parameters coming from several experimental limits. Asymmetries of several percent are obtained. We also comment on the feasibility of measuring this asymmetry at the LHC.