A search for the B0âK+K- decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb-1 at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the Bs0âÏ+Ï- decay. The measured branching fractions are B(B0âK+K-)=(7.80±1.27±0.81±0.21)Ã10-8 and B(Bs0âÏ+Ï-)=(6.91±0.54±0.63±0.19±0.40)Ã10-7. The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B0âK+Ï- branching fraction used as a normalization. For the Bs0 mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into Bs0 and B0 mesons.
Observation of the Annihilation Decay Mode B0 -> k+K-
De Serio, M.;Pappagallo, M.;Simone, S.;
2017-01-01
Abstract
A search for the B0âK+K- decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb-1 at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the Bs0âÏ+Ï- decay. The measured branching fractions are B(B0âK+K-)=(7.80±1.27±0.81±0.21)Ã10-8 and B(Bs0âÏ+Ï-)=(6.91±0.54±0.63±0.19±0.40)Ã10-7. The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B0âK+Ï- branching fraction used as a normalization. For the Bs0 mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into Bs0 and B0 mesons.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.