The nuclear modification factors of J/psi and psi(2S) mesons are measured in PbPb collisions at a centre-of-mass energy per nucleon pair of root S-NN = 5.02 TeV. The analysis is based on PbPb and pp data samples collected by CMS at the LHC in 2015, corresponding to integrated luminosities of 464 mu b(-1) and 28 pb(-1), respectively. The measurements are performed in the dimuon rapidity range of vertical bar y vertical bar < 2.4 as a function of centrality, rapidity, and transverse momentum (p(T)) from p(T) = 3 GeV/c in the most forward region and up to 50 GeV/c. Both prompt and nonprompt (coming from b hadron decays) J/psi mesons are observed to be increasingly suppressed with centrality, with a magnitude similar to the one observed at root S-NN = 2.76 TeV for the two J/psi meson components. No dependence on rapidity is observed for either prompt or nonprompt J/psi mesons. An indication of a lower prompt J/psi meson suppression at p(T) > 25 GeV/c is seen with respect to that observed at intermediate p(T). The prompt psi(2S) meson yield is found to be more suppressed than that of the prompt J/psi mesons in the entire p(T) range.
Measurement of prompt and nonprompt charmonium suppression in PbPb collisions at 5.02 TeV
Azzi, P.;Benato, L.;Bisello, D.;Boletti, A.;Carlin, R.;De Oliveira, A. Carvalho Antunes;Checchia, P.;Dall'Osso, M.;Gasparini, F.;Gasparini, U.;Lacaprara, S.;Lujan, P.;Meneguzzo, A. T.;Pantano, D.;Pozzobon, N.;Ronchese, P.;Rossin, R.;Simonetto, F.;Torassa, E.;Zanetti, M.;Zotto, P.;Zumerle, G.;Tosi, M.;Triossi, A.;Pazzini, J.;
2018
Abstract
The nuclear modification factors of J/psi and psi(2S) mesons are measured in PbPb collisions at a centre-of-mass energy per nucleon pair of root S-NN = 5.02 TeV. The analysis is based on PbPb and pp data samples collected by CMS at the LHC in 2015, corresponding to integrated luminosities of 464 mu b(-1) and 28 pb(-1), respectively. The measurements are performed in the dimuon rapidity range of vertical bar y vertical bar < 2.4 as a function of centrality, rapidity, and transverse momentum (p(T)) from p(T) = 3 GeV/c in the most forward region and up to 50 GeV/c. Both prompt and nonprompt (coming from b hadron decays) J/psi mesons are observed to be increasingly suppressed with centrality, with a magnitude similar to the one observed at root S-NN = 2.76 TeV for the two J/psi meson components. No dependence on rapidity is observed for either prompt or nonprompt J/psi mesons. An indication of a lower prompt J/psi meson suppression at p(T) > 25 GeV/c is seen with respect to that observed at intermediate p(T). The prompt psi(2S) meson yield is found to be more suppressed than that of the prompt J/psi mesons in the entire p(T) range.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.