Measurement of the -violating Phase In the Channel in Proton-proton Collisions at
A.M. Sirunyan (Yerevan Physics Institute, Yerevan, Armenia); A. Tumasyan (Yerevan Physics Institute, Yerevan, Armenia); W. Adam (Institut für Hochenergiephysik, Wien, Austria); F. Ambrogi (Institut für Hochenergiephysik, Wien, Austria); T. Bergauer (Institut für Hochenergiephysik, Wien, Austria); et al - Show all 2382 authors
The CP -violating weak phase and the decay width difference between the light and heavy mass eigenstates are measured with the CMS detector at the LHC in a sample of reconstructed events. The measurement is based on a data sample corresponding to an integrated luminosity of , collected in proton-proton collisions at in 2017–2018. To extract the values of and , a time-dependent and flavor-tagged angular analysis of the final state is performed. The analysis employs a dedicated tagging trigger and a novel opposite-side muon flavor tagger based on machine learning techniques. The measurement yields and , in agreement with the standard model predictions. When combined with the previous CMS measurement at , the following values are obtained: , , a significant improvement over the 8 TeV result.