Measurement of nuclear modification factors of ϒ(1S), ϒ(2S), and ϒ(3S) mesons in PbPb collisions at √sNN = 5.02 TeV
The cross sections for ϒ(1S), ϒ(2S), and ϒ(3S) production in lead–lead (PbPb) and proton–proton (pp) collisions at √sNN = 5.02 TeV have been measured using the CMS detector at the LHC. The nuclear modification factors, RAA, derived from the PbPb-to-pp ratio of yields for each state, are studied as...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English English English |
| Published: |
Elsevier B.V.
2019
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| Subjects: | |
| Online Access: | http://irep.iium.edu.my/71724/ http://irep.iium.edu.my/71724/ http://irep.iium.edu.my/71724/ http://irep.iium.edu.my/71724/1/71724_Measurement%20of%20nuclear%20modification%20factors_article.pdf http://irep.iium.edu.my/71724/2/71724_Measurement%20of%20nuclear%20modification%20factors_wos.pdf http://irep.iium.edu.my/71724/3/71724_Measurement%20of%20nuclear%20modification%20factors_scopus.pdf |
| Summary: | The cross sections for ϒ(1S), ϒ(2S), and ϒ(3S) production in lead–lead (PbPb) and proton–proton (pp)
collisions at √sNN = 5.02 TeV have been measured using the CMS detector at the LHC. The nuclear
modification factors, RAA, derived from the PbPb-to-pp ratio of yields for each state, are studied as
functions of meson rapidity and transverse momentum, as well as PbPb collision centrality. The yields of
all three states are found to be significantly suppressed, and compatible with a sequential ordering of the
suppression, RAA(ϒ(1S)) > RAA(ϒ(2S)) > RAA(ϒ(3S)). The suppression of ϒ(1S) is larger than that seen
at √sNN = 2.76 TeV, although the two are compatible within uncertainties. The upper limit on the RAA of
ϒ(3S) integrated over pT, rapidity and centrality is 0.096 at 95% confidence level, which is the strongest
suppression observed for a quarkonium state in heavy ion collisions to date. |
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