Angular analysis of the decay B$^+$ $\to$ K$^+\mu^+\mu^-$ in proton-proton collisions at $\sqrt{s} =$ 8 TeV

TL;DR

This paper presents an angular analysis of the decay B+ to K+ mu+ mu- in proton-proton collisions at 8 TeV, measuring asymmetries and contributions that align with Standard Model predictions.

Contribution

It provides the first detailed measurement of angular observables in B+ to K+ mu+ mu- decays at 8 TeV, testing the Standard Model with new data.

Findings

Measured forward-backward asymmetry A_FB consistent with Standard Model

Determined contribution F_H from various amplitudes matching theoretical expectations

Analyzed decay width as a function of dimuon mass squared

Abstract

The angular distribution of the flavor-changing neutral current decay B$^+$ $\to$ K$^+\mu^+\mu^-$ is studied in proton-proton collisions at a center-of-mass energy of 8 TeV. The analysis is based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 20.5 fb$^{-1}$. The forward-backward asymmetry $A_{\mathrm{FB}}$ of the dimuon system and the contribution $F_{\mathrm{H}}$ from the pseudoscalar, scalar, and tensor amplitudes to the decay width are measured as a function of the dimuon mass squared. The measurements are consistent with the standard model expectations.