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arXiv · 1710.02846

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

CMS Collaboration
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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.

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CMS Collaboration. 2017-10-08. 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. https://doi.org/10.1016/j.physletb.2018.04.030

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