Measurement of angular parameters from the decay $\mathrm{B}^0 \to \mathrm{K}^{*0} \mu^+ \mu^-$ in proton-proton collisions at $\sqrt{s} = $ 8 TeV

TL;DR

This paper measures angular parameters in the decay of B0 mesons to K*0 mu+ mu- using 8 TeV proton-proton collision data, testing for deviations from the Standard Model predictions.

Contribution

First detailed angular analysis of B0 to K*0 mu+ mu- decay at 8 TeV, focusing on P1 and P5' parameters with a large data sample.

Findings

Results agree with Standard Model predictions.

No significant discrepancy observed in P5' parameter.

Provides precise measurements across dimuon mass range.

Abstract

Angular distributions of the decay $\mathrm{B}^0 \to \mathrm{K}^{*0} \mu^+ \mu^-$ are studied using a sample of proton-proton collisions at $\sqrt{s} = $ 8 TeV collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 20.5 fb$^{-1}$. An angular analysis is performed to determine the $P_1$ and $P_5'$ parameters, where the $P_5'$ parameter is of particular interest because of recent measurements that indicate a potential discrepancy with the standard model predictions. Based on a sample of 1397 signal events, the $P_1$ and $P_5'$ parameters are determined as a function of the dimuon invariant mass squared. The measurements are in agreement with predictions based on the standard model.