Centrality and transverse momentum dependence of inclusive J/ψ production at midrapidity in Pb-Pb collisions at √{sNN } = 5.02 TeV
Abstract
The inclusive J / ψ meson production in Pb-Pb collisions at a center-of-mass energy per nucleon-nucleon collision of √{sNN } = 5.02 TeV at midrapidity (| y | < 0.9) is reported by the ALICE Collaboration. The measurements are performed in the dielectron decay channel, as a function of event centrality and J / ψ transverse momentum pT, down to pT = 0. The J / ψ mean transverse momentum «pT » and rAA ratio, defined as « pT2 » PbPb /« pT2 » pp, are evaluated. Both observables show a centrality dependence decreasing towards central (head-on) collisions. The J / ψ nuclear modification factor RAA exhibits a strong pT dependence with a large suppression at high pT and an increase to unity for decreasing pT. When integrating over the measured momentum range pT < 10GeV / c, the J / ψRAA shows a weak centrality dependence. Each measurement is compared with results at lower center-of-mass energies and with ALICE measurements at forward rapidity, as well as to theory calculations. All reported features of the J / ψ production at low pT are consistent with a dominant contribution to the J / ψ yield originating from charm quark (re)combination.
- Publication:
-
Physics Letters B
- Pub Date:
- June 2020
- DOI:
- 10.1016/j.physletb.2020.135434
- arXiv:
- arXiv:1910.14404
- Bibcode:
- 2020PhLB..80535434A
- Keywords:
-
- Nuclear Experiment;
- High Energy Physics - Experiment
- E-Print:
- 24 pages, 8 captioned figures, 2 tables, authors from page 19, published version, figures at http://alice-publications.web.cern.ch/node/5653