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arXiv · 1109.1850

Dimuon results in PbPb and pp collisions in CMS

Manuel Calderón de la Barca Sánchez
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Abstract

The LHC offers unique opportunities for studying the properties of hot QCD matter created in Pb+Pb collisions at extreme temperatures and very low parton momentum fractions. With its high precision, large acceptance for tracking and calorimetry, and a trigger scheme that allows analysis of each minimum bias Pb+Pb event, CMS is fully equipped to measure dimuons in the high multiplicity environment of Pb+Pb collisions. Such probes are especially relevant since they are produced at early times and propagate through the medium, mapping its evolution. The capabilities of the CMS experiment to study dimuon production in pp and Pb+Pb collisions based on the 2010 LHC runs will be reviewed. CMS is able to measure primary and secondary J/psi, as well as the three Upsilon states. Quarkonia results at sqrt(s)=2.76 TeV in pp and Pb+Pb will be presented, including a tantalizing observation of suppression of the Upsilon excited states. The Z0 boson inclusive and differential measurement as a probe of the initial state will be described.

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Manuel Calderón de la Barca Sánchez. 2011-09-08. Dimuon results in PbPb and pp collisions in CMS. https://doi.org/10.1063/1.3700699

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