Time-dependent angular analysis of the decay B0 s ????????? J / ?????? ?????? and extraction of ???????????? s and the CP-violating weak phase ?????? s by ATLAS

A measurement of B0 s ????????? J /???????????? decay parameters, including the CP -violating weak phase ?????? s and the decay width difference ???????????? s is reported, using 4.9 fb-1 of integrated luminosity collected in 2011 by the ATLAS detector from LHC pp collisions at a centre-of-mass energy ?????????s = 7 TeV. The mean decay width ?????? s and the transversity amplitudes |A 0(0)|2 and |A arap;(0)|2 are also measured. The values reported for these parameters are: ??????s = 0.22 ?????? 0.41 (stat) ?????? 0.10 (syst) rad ???????????? s = 0.053 ?????? 0.021 (stat) ?????? 0.010 (sast) ps-1 ?????? s = 0.677 ?????? 0.007 (stat) ?????? 0.004 (sast) ps-1 |A0(0)|2 = 0.528 ?????? 0.006 (stat) ?????? 0.009 (sast) |A0(0)|2 = 0.220 ?????? 0.008 (stat) ?????? 0.007 (sast) where the values quoted for ?????? s and ???????????? s correspond to the solution compatible with the external measurements to which the strong phase ?????? ?????????????????? is constrained and where ???????????? s is constrained to be positive. The fraction of S-wave KK or f 0 contamination through the decays B0 s????????? J /??????K + K-f-0 is measured as well and is found to be consistent with zero. Results for ?????? s and ???????????? s are also presented as 68%, 90% and 95% likelihood contours, which show agreement with Standard Model expectations.[Figure not available: see fulltext.] ?????? 2012 CERN for the benefit of the ATLAS collaboration.