Abstract: Results are reported for the B0s ? ?+?- branching fraction and effective lifetime and from a search for the decay B0? ?+?-. The analysis uses a data sample of proton-proton collisions accumulated by the CMS experiment in 2011, 2012, and 2016, with center-of-mass energies (integrated luminosities) of 7 TeV (5 fb-1), 8 TeV (20 fb-1), and 13 TeV (36 fb-1). The branching fractions are determined by measuring event yields relative to B+? J/?K+ decays (with J/? ? ?+?-), which results in the reduction of many of the systematic uncertainties. The decay B0s ? ?+?- is observed with a significance of 5.6 standard deviations. The branching fraction is measured to be B(B0s??+?-)=[2.9±0.7(exp)±0.2(frag)]×10-9B(Bs0??+?-)=[2.9±0.7(exp)±0.2(frag)]×10-9 , where the first uncertainty combines the experimental statistical and systematic contributions, and the second is due to the uncertainty in the ratio of the B0sBs0 and the B+ fragmentation functions. No significant excess is observed for the decay B0? ?+?-, and an upper limit of ?(B0????+?-)?

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