Measurement of the CP-violating weak phase Ï s and the decay width difference ÎÎ s using the Bs0âJ/ÏÏ(1020) decay channel in pp collisions at s=8Â TeV
V. Khachatryan (Yerevan Physics Institute, Yerevan, Armenia); A.M. Sirunyan (Yerevan Physics Institute, Yerevan, Armenia); A. Tumasyan (Yerevan Physics Institute, Yerevan, Armenia); W. Adam (Institut für Hochenergiephysik der OeAW, Wien, Austria); E. Asilar (Institut für Hochenergiephysik der OeAW, Wien, Austria); et al - Show all 2311 authors
The CP-violating weak phase Ïs of the Bs0 meson and the decay width difference ÎÎs of the Bs0 light and heavy mass eigenstates are measured with the CMS detector at the LHC using a data sample of Bs0âJ/ÏÏ(1020)âμ+μâK+Kâ decays. The analysed data set corresponds to an integrated luminosity of 19.7fbâ1 collected in pp collisions at a centre-of-mass energy of 8TeV . A total of 49â200 reconstructed Bs0 decays are used to extract the values of Ïs and ÎÎs by performing a time-dependent and flavour-tagged angular analysis of the μ+μâK+Kâ final state. The weak phase is measured to be Ïs=â0.075±0.097(stat)±0.031(syst) rad , and the decay width difference is ÎÎs=0.095±0.013(stat)±0.007(syst) psâ1 .
