https://doi.org/10.1051/epjconf/201714108007
Measurement of bottomonium states in pp, pPb and PbPb collisions at 2.76 TeV from CMS
Korea University, 145 Anam-ro, Seonbuk-gu, Seoul, Republic of Korea
a e-mail: jaebeom.park@cern.ch
Published online: 12 April 2017
The bottomonium states are one of the cleanest probes to study the characteristics of the quark-gluon plasma (QGP) as they are produced through hard scattering at the early stage of the collision. Their relative production cross section in PbPb collisions compared to pp collisions, the nuclear modification factor RAA, has been studied and strong suppression was found in PbPb collisions. The RAA has been obtained in centrality intervals for ϒ(1S) & ϒ(2S) and also reported as a function of pT and rapidity. Also the yield ratios of the excited states ϒ(nS) compared to the ground state ϒ(1S) in both pp and PbPb collisions are combined to form the double ratio, which is equivalent to the ratio of the nuclear modification factor RAA. This quantity has been studied for the two excited states ϒ(2S) and ϒ(3S) in pPb and PbPb collisions.
© The Authors, published by EDP Sciences, 2017
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