Measurement of the CP violating phase $\Phi_s$ with CMS and ATLAS

TL;DR

This paper reports on measurements of the CP-violating phase _s in B_s meson decays using data from CMS and ATLAS, providing insights into CP violation in the B_s system.

Contribution

First combined analysis of _s phase using CMS and ATLAS data from LHC Run1 in the B_s  J/  decay channel.

Findings

Measurement of _s consistent with Standard Model predictions.

Improved precision over previous measurements.

Constraints on new physics contributions to CP violation.

Abstract

The phase $\Phi_s$ is the key parameter for the CP-violation of the $B^0_s$-$\bar{B^0_s}$ system. An angular and proper decay time analysis is applied to the $B^0_s \rightarrow J/\psi \Phi$ events. Using a data sample collected by the CMS and ATLAS experiments in LHC Run1, the $B^0_s$ signal candidates are reconstructed and are used to extract the phase $\Phi_s$. We present the latest update on the results in this decay channel.