Yields of prompt and non-prompt J/ψ, as well as (1S) mesons, are measured by the CMS experiment via their μ + μ − decays in PbPb and pp collisions at sNN=276 TeV for quarkonium rapidity |y| < 2.4. Differential cross sections and nuclear modification factors are reported as functions of y and transverse momentum p T, as well as collision centrality. For prompt J/ψ with relatively high p T (6.5 < p T < 30 GeV/c), a strong, centrality-dependent suppression is observed in PbPb collisions, compared to the yield in pp collisions scaled by the number of inelastic nucleon-nucleon collisions. In the same kinematic range, a suppression of non-prompt J/ψ, which is sensitive to the in-medium b-quark energy loss, is measured for the first time. Also the low-p T (1S) mesons are suppressed in PbPb collisions.
Suppression of non-prompt J/ψ, prompt J/ψ, and $ \Upsilon $ (1S) in PbPb collisions at $ \sqrt {{{s_{\text{NN}}}}} = 2.76 $ TeV
TOSI, SILVANO;
2012-01-01
Abstract
Yields of prompt and non-prompt J/ψ, as well as (1S) mesons, are measured by the CMS experiment via their μ + μ − decays in PbPb and pp collisions at sNN=276 TeV for quarkonium rapidity |y| < 2.4. Differential cross sections and nuclear modification factors are reported as functions of y and transverse momentum p T, as well as collision centrality. For prompt J/ψ with relatively high p T (6.5 < p T < 30 GeV/c), a strong, centrality-dependent suppression is observed in PbPb collisions, compared to the yield in pp collisions scaled by the number of inelastic nucleon-nucleon collisions. In the same kinematic range, a suppression of non-prompt J/ψ, which is sensitive to the in-medium b-quark energy loss, is measured for the first time. Also the low-p T (1S) mesons are suppressed in PbPb collisions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.