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Title: Systematic study of azimuthal anisotropy in Cu + Cu and Au + Au collisions at √sNN = 62.4 and 200 GeV

We have studied the dependence of azimuthal anisotropy v2 for inclusive and identified charged hadrons in Au+Au and Cu+Cu collisions on collision energy, species, and centrality. The values of v2 as a function of transverse momentum pT and centrality in Au+Au collisions at √sNN=200 and 62.4 GeV are the same within uncertainties. However, in Cu+Cu collisions we observe a decrease in v2 values as the collision energy is reduced from 200 to 62.4 GeV. The decrease is larger in the more peripheral collisions. By examining both Au+Au and Cu+Cu collisions we find that v2 depends both on eccentricity and the number of participants, Npart. We observe that v2 divided by eccentricity (ε) monotonically increases with Npart and scales as N1/3part. Thus, the Cu+Cu data at 62.4 GeV falls below the other scaled v2 data. For identified hadrons, v2 divided by the number of constituent quarks nq is independent of hadron species as a function of transverse kinetic energy KET=mT–m between 0.1T/nq<1 GeV. Combining all of the above scaling and normalizations, we observe a near-universal scaling, with the exception of the Cu+Cu data at 62.4 GeV, of v2/(nq∙ε∙N1/3part) vs KET/nq for all measured particles.
  1. Univ. of Colorado, Boulder, CO (United States). et al.
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 0556-2813; PRVCAN; KB201021
Grant/Contract Number:
SC00112704; AC05-00OR22725
Accepted Manuscript
Journal Name:
Physical Review. C, Nuclear Physics
Additional Journal Information:
Journal Volume: 92; Journal Issue: 3; Journal ID: ISSN 0556-2813
American Physical Society (APS)
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
Contributing Orgs:
PHENIX Collaboration
Country of Publication:
United States
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; RHIC; azimuthal; anisotropy; Cu+Cu and Au+Au; collisions; Relativistic Heavy Ion Collider