Angular analysis of the decay B$^+$ $\to$ K$^*$(892)$^+\mu^+\mu^-$ in proton-proton collisions at $\sqrt{s} =$ 8 TeV

TL;DR

This paper presents the first angular analysis of the decay B$^+$ $ o$ K$^*$(892)$^+m in proton-proton collisions at 8 TeV, measuring asymmetries and polarization consistent with the Standard Model.

Contribution

First measurement of angular distributions in B$^+$ $ o$ K$^*$(892)$^+m decay at LHC, providing key tests of the Standard Model.

Findings

Results agree with Standard Model predictions.

First measurement of this decay mode's angular observables.

Provides baseline for future new physics searches.

Abstract

Angular distributions of the decay B$^+$ $\to$ K$^*$(892)$^+\mu^+\mu^-$ are studied using events collected with the CMS detector in $\sqrt{s} =$ 8 TeV proton-proton collisions at the LHC, corresponding to an integrated luminosity of 20.0 fb$^{-1}$. The forward-backward asymmetry of the muons and the longitudinal polarization of the K$^*$(892)$^+$ meson are determined as a function of the square of the dimuon invariant mass. These are the first results from this exclusive decay mode and are in agreement with a standard model prediction.