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

We have studied the dependence of azimuthal anisotropy v 2 for inclusive and identified charged hadrons in Au+Au and Cu+Cu collisions on collision energy, species, and centrality. The values of v 2 as a function of transverse momentum pT and centrality in Au+Au collisions at √s NN=200 and 62.4 GeV are the same within uncertainties. However, in Cu+Cu collisions we observe a decrease in v 2 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 v 2 depends both on eccentricity and the number of participants, N part. We observe that v 2 divided by eccentricity (ε) monotonically increases with N part and scales as N 1/3 part. Thus, the Cu+Cu data at 62.4 GeV falls below the other scaled v 2 data. For identified hadrons, v 2 divided by the number of constituent quarks nq is independent of hadron species as a function of transverse kinetic energy KE T=m T–m between 0.1T/n q<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,more » of v 2/(n q∙ε∙N 1/3 part) vs KE T/n q for all measured particles.« less
Authors:
 [1]
  1. Univ. of Colorado, Boulder, CO (United States). et al.
Publication Date:
Report Number(s):
BNL-108444-2015-JA
Journal ID: ISSN 0556-2813; PRVCAN; KB201021
Grant/Contract Number:
SC00112704; AC05-00OR22725
Type:
Accepted Manuscript
Journal Name:
Physical Review. C, Nuclear Physics
Additional Journal Information:
Journal Volume: 92; Journal Issue: 3; Journal ID: ISSN 0556-2813
Publisher:
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
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; RHIC; azimuthal; anisotropy; Cu+Cu and Au+Au; collisions; Relativistic Heavy Ion Collider
OSTI Identifier:
1226055
Alternate Identifier(s):
OSTI ID: 1224623; OSTI ID: 1324142