The first observation of the decays Îb0âÏc1pK- and Îb0âÏc2pK- is reported using a data sample corresponding to an integrated luminosity of 3.0 fb-1, collected by the LHCb experiment in pp collisions at center-of-mass energies of 7 and 8 TeV. The following ratios of branching fractions are measured: B(Îb0âÏc1pK-)B(Îb0âJ/ÏpK-)=0.242±0.014±0.013±0.009,B(Îb0âÏc2pK-)B(Îb0âJ/ÏpK-)=0.248±0.020±0.014±0.009,B(Îb0âÏc2pK-)B(Îb0âÏc1pK-)=1.02±0.10±0.02±0.05,where the first uncertainty is statistical, the second systematic, and the third due to the uncertainty on the branching fractions of the Ïc1âJ/Ïγ and Ïc2âJ/Ïγ decays. Using both decay modes, the mass of the Îb0 baryon is also measured to be mÎb0=5619.44±0.28±0.26 MeV/c2, where the first and second uncertainties are statistical and systematic, respectively.
Observation of the Decays Λb0 →χc1pK- and Λb0 →χc2pK-
De Serio, M.;Pappagallo, M.;
2017-01-01
Abstract
The first observation of the decays Îb0âÏc1pK- and Îb0âÏc2pK- is reported using a data sample corresponding to an integrated luminosity of 3.0 fb-1, collected by the LHCb experiment in pp collisions at center-of-mass energies of 7 and 8 TeV. The following ratios of branching fractions are measured: B(Îb0âÏc1pK-)B(Îb0âJ/ÏpK-)=0.242±0.014±0.013±0.009,B(Îb0âÏc2pK-)B(Îb0âJ/ÏpK-)=0.248±0.020±0.014±0.009,B(Îb0âÏc2pK-)B(Îb0âÏc1pK-)=1.02±0.10±0.02±0.05,where the first uncertainty is statistical, the second systematic, and the third due to the uncertainty on the branching fractions of the Ïc1âJ/Ïγ and Ïc2âJ/Ïγ decays. Using both decay modes, the mass of the Îb0 baryon is also measured to be mÎb0=5619.44±0.28±0.26 MeV/c2, where the first and second uncertainties are statistical and systematic, respectively.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.