CMS collaboration (2266 authors)Nayak, ArunaBargassa, PedrameBeirão Da Cruz E Silva, CristóvãoDi Francesco, AgostinoFaccioli, PietroGalinhas, BrunoGallinaro, MicheleHollar, JonathanLeonardo, NunoLloret Iglesias, LaraSeixas, JoaoStrong, GilesToldaiev, OleksiiVadruccio, DanieleVarela, JoaoVischia, PietroDavid Tinoco Mendes, AndreSilva, PedroMusella, Pasquale2019-02-052019-02-052018-06-10http://dx.doi.org/10.1016/j.physletb.2018.04.030http://hdl.handle.net/10400.26/27471Angular distributions of the decay B0→K⁎0μ+μ− are studied using a sample of proton–proton collisions at s=8TeV collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 20.5fb−1 . An angular analysis is performed to determine the P1 and P5′ parameters, where the P5′ 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 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.engjournal article2019-02-05