Seminarium Fizyki Wielkich Energii

The smallest deviation from the precise value of the CP-violating weak phase predicted by Standard Model in the B_s to Jpsiphi decay mode would hint for a new domain of physics. Also improving precision with higher statistics of the Run-II proton-proton collision data collected by CMS detector may help to constrain the future theories. These were the motivations of measuring the weak phase in the B_s to Jpsiphi decay. In this talk we will see how the weak phase measurement is done with ~97fb^-1 of the 13TeV proton-proton collision data and what level of precision is achieved.