Observation of an Energy-Dependent Difference in Elliptic Flow between Particles and Antiparticles in Relativistic Heavy Ion Collisions

• Main Authors: Balewski, Jan T. (Contributor), Betancourt, Michael Joseph (Contributor), Corliss, Ross (Contributor), Hays-Wehle, James Prewitt (Contributor), Leight, William Axel (Contributor), Stevens, Justin (Contributor), van Nieuwenhuizen, Gerrit Jan (Contributor)
• Other Authors: Massachusetts Institute of Technology. Laboratory for Nuclear Science (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2013-09-19T13:53:54Z.
• Subjects: Article
• Online Access: Get fulltext

Elliptic flow (v[subscript 2]) values for identified particles at midrapidity in Au+Au collisions, measured by the STAR experiment in the beam energy scan at RHIC at √s[subscript NN]=7.7-62.4  GeV, are presented. A beam-energy-dependent difference of the values of v[subscript 2] between particles and corresponding antiparticles was observed. The difference increases with decreasing beam energy and is larger for baryons compared to mesons. This implies that, at lower energies, particles and antiparticles are not consistent with the universal number-of-constituent-quark scaling of v2 that was observed at √sNN=200  GeV.
United States. Dept. of Energy. Office of High Energy Physics
United States. Dept. of Energy. Office of Nuclear Physics
Alfred P. Sloan Foundation
National Science Foundation (U.S.)
Brookhaven National Laboratory. RHIC Operations Group