Recent diboson and polarization measurements at CMS

Over the course Run 1 and Run 2 of the Large Hadron Collider (LHC), more than 150/fb of data has been collected by the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider. This large dataset has facilitated the precision measurement of several Standard Model (SM) processes. Diboson processes, where two gauge bosons are simultaneously produced in one LHC collision event, fall within the category of processes that can be measured with precision. These processes feature the trilinear gauge coupling and provide important tests of the non-Abelian gauge structure of the SM. The measurement of properties of the gauge boson, such as the polarization, can be carried out with these processes. The first measurement of longitudinally polarized W-bosons was performed by the CMS Collaboration in the study of the fully leptonic decays of the gauge bosons in a WZ process. The novel technique of tagging protons using the precision proton spectrometer enables the precision studies of dibosons produced in photon-induced processes, allowing unique access to the quartic coupling between photons and gauge bosons. Finally, a comprehensive measurement of the polarization of the 𝜏 lepton in a final state where the Z-boson decays to pairs of 𝜏 leptons is presented. The precision on the measured value of the 𝜏 polarization surpasses previous measurements at the LHC.