Like-sign dimuon charge asymmetry in Randall-Sundurm model

TL;DR

This paper investigates whether the Randall-Sundrum model can explain the DØ dimuon charge asymmetry anomaly, finding it cannot fully account for the observed effect due to limitations in generating sufficient width difference contributions.

Contribution

The study analyzes the impact of warped geometry Randall-Sundrum models on dimuon asymmetry, highlighting their inability to fully explain the DØ anomaly due to constraints on width difference contributions.

Findings

Model alters the wrong charge asymmetry significantly.

Experimental constraints limit the model's ability to match the observed asymmetry.

Model cannot generate enough contribution to the width difference $ ext{Gamma}_{12}^s$.

Abstract

We confirm that in order to account for the recent D\O\ result of large like-sign dimuon charge asymmetry, a considerable large new physics effect in $\Gamma_{12}^s$ is required in addition to a large CP violating phase in $B_s -\bar{B}_s$ mixing. In the Randall-Sundrum model of warped geometry, where the fermion fields reside in the bulk, new sources of flavor and CP violation are obtained. We analyze the like-sign dimuon asymmetry in this class of model, as an example of the desired new physics. We show that the wrong charge asymmetry, $a_{sl}^s$, which is related to the dimuon asymmetry, is significantly altered compared to the Standard Model value. However, experimental limits from $\Delta M_s$, $\Delta\Gamma_s$ as well as $K$ mixing and electroweak corrections constrain it to be greater than a $\sigma$ away from its experimental average value. This model cannot fully account for the D\O\ anomaly due to its inability to generate sufficient new contribution to the width difference $\Gamma^s_{12}$, even though the model can generate large contribution to the mass difference $M^s_{12}$.