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arXiv · 1108.5077

Quarkonia Measurements by the CMS Experiment in pp and PbPb Collisions

Catherine Silvestre
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Abstract

Quarkonia have been studied in different collision system and energy in order to understand the effects of the hot and dense medium created in heavy-ion collisions. CMS is well suited to measure quarkonia decays to muons given the muon identification and charged particle tracking capability. We report here prompt, non-prompt J/ψ, and Υ production measured by the CMS experiment in pp collisions at \sqrt{s}=7 TeV. In addition, the J/ψ and Υ production in PbPb at \sqrt{s_{NN}}=2.76 TeV and pp collisions at the same per nucleon energy are measured and compared. Prompt and non-prompt J/ψ contributions are separated for the first time in heavy-ion collisions, as is the ground from the excited states in the Υ family. Suppression in PbPb at \sqrt{s_{NN}}=2.76 TeV is quantified for prompt J/ψ, B->J/ψ, and Υ(1S), as well as the relative suppression of Υ(2S+3S) compared to Υ(1S).

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Catherine Silvestre. 2011-08-25. Quarkonia Measurements by the CMS Experiment in pp and PbPb Collisions. https://doi.org/10.1088/0954-3899%2F38%2F12%2F124033

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