An observation of the Lambda0b->psi(2S)Lambda0 decay and a comparison of its branching fraction with that of the Lambda0b->J/psiLambda0 decay has been made with the ATLAS detector in proton--proton collisions at sqrt(s)=8TeV at the LHC using an integrated luminosity of 20.6fb-1. The J/? and ?(2S) mesons are reconstructed in their decays to a muon pair, while the ?0?pp- decay is exploited for the ?0 baryon reconstruction. The ?0b baryons are reconstructed with transverse momentum pT>10GeV and pseudorapidity |eta|<2.1. The measured branching ratio of the Lambda0b->psi(2S)Lambda0 and Lambda0b->J/psiLambda0 decays is G(?0b??(2S)?0)/G(?0b?J/??0)=0.501±0.033(stat)±0.019(syst), lower than the expectation from the covariant quark model.
Measurement of the branching ratio Gamma(Lambda0b->psi(2S)Lambda0)/Gamma(Lambda0b->J/psiLambda0) with the ATLAS detector
CHIODINI, GABRIELE;GORINI, Edoardo;PRIMAVERA, Margherita;SPAGNOLO, Stefania Antonia;VENTURA, Andrea;
2015-01-01
Abstract
An observation of the Lambda0b->psi(2S)Lambda0 decay and a comparison of its branching fraction with that of the Lambda0b->J/psiLambda0 decay has been made with the ATLAS detector in proton--proton collisions at sqrt(s)=8TeV at the LHC using an integrated luminosity of 20.6fb-1. The J/? and ?(2S) mesons are reconstructed in their decays to a muon pair, while the ?0?pp- decay is exploited for the ?0 baryon reconstruction. The ?0b baryons are reconstructed with transverse momentum pT>10GeV and pseudorapidity |eta|<2.1. The measured branching ratio of the Lambda0b->psi(2S)Lambda0 and Lambda0b->J/psiLambda0 decays is G(?0b??(2S)?0)/G(?0b?J/??0)=0.501±0.033(stat)±0.019(syst), lower than the expectation from the covariant quark model.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
