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

Angular distributions of the decay B0 → K∗0 µ+ µ− are studied using a sample of proton-proton collisions at 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 P1 and P5 parameters, where parameter is of particular interest because of recent measurements the P5 that indicate a potential discrepancy with the standard model predictions. Based on a sample of 1397 signal events, the P1 and P5 parameters are determined as a function of the dimuon invariant mass squared. The measurements are in agreement with predictions based on the standard model.