Suppression of Excited ϒ States Relative to the Ground State in Pb-Pb Collisions at √{s} NN=5.02 TeV
Abstract
The relative yields of ϒ mesons produced in p p and Pb-Pb collisions at √{sNN }=5.02 TeV and reconstructed via the dimuon decay channel are measured using data collected by the CMS experiment. Double ratios are formed by comparing the yields of the excited states, ϒ (2 S ) and ϒ (3 S ), to the ground state, ϒ (1 S ), in both Pb-Pb and p p collisions at the same center-of-mass energy. The double ratios, [ϒ (nS ) /ϒ (1 S ) ]Pb-Pb/[ϒ (nS ) /ϒ (1 S ) ]pp, are measured to be 0.308 ±0.055 (stat ) ±0.019 (syst ) for the ϒ (2 S ) and less than 0.26 at 95% confidence level for the ϒ (3 S ). No significant ϒ (3 S ) signal is found in the Pb-Pb data. The double ratios are studied as a function of collision centrality, as well as ϒ transverse momentum and rapidity. No significant dependencies are observed.
- Publication:
-
Physical Review Letters
- Pub Date:
- April 2018
- DOI:
- 10.1103/PhysRevLett.120.142301
- arXiv:
- arXiv:1706.05984
- Bibcode:
- 2018PhRvL.120n2301S
- Keywords:
-
- High Energy Physics - Experiment;
- Nuclear Experiment
- E-Print:
- Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/HIN-16-008 (CMS Public Pages)