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Title: Mass, quark-number, and {radical}(s{sub NN}) dependence of the second and fourth flow harmonics in ultrarelativistic nucleus-nucleus collisions

Abstract

We present STAR measurements of the azimuthal anisotropy parameter v{sub 2} for pions, kaons, protons, {lambda},{lambda},{xi}+{xi}, and {omega}+{omega}, along with v{sub 4} for pions, kaons, protons, and {lambda}+{lambda} at midrapidity for Au+Au collisions at {radical}(s{sub NN})=62.4 and 200 GeV. The v{sub 2}(p{sub T}) values for all hadron species at 62.4 GeV are similar to those observed in 130 and 200 GeV collisions. For observed kinematic ranges, v{sub 2} values at 62.4, 130, and 200 GeV are as little as 10-15% larger than those in Pb+Pb collisions at {radical}(s{sub NN})=17.3 GeV. At intermediate transverse momentum (p{sub T} from 1.5-5 GeV/c), the 62.4 GeV v{sub 2}(p{sub T}) and v{sub 4}(p{sub T}) values are consistent with the quark-number scaling first observed at 200 GeV. A four-particle cumulant analysis is used to assess the nonflow contributions to pions and protons and some indications are found for a smaller nonflow contribution to protons than pions. Baryon v{sub 2} is larger than antibaryon v{sub 2} at 62.4 and 200 GeV, perhaps indicating either that the initial spatial net-baryon distribution is anisotropic, that the mechanism leading to transport of baryon number from beam- to midrapidity enhances v{sub 2} or that antibaryon and baryon annihilation is larger inmore » the in-plane direction.« less

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;  [1]
  1. Yale University, New Haven, Connecticut 06520 (United States) (and others)
Publication Date:
OSTI Identifier:
20995310
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevC.75.054906; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ANNIHILATION; ANTIBARYONS; BARYON NUMBER; COLLISIONS; GEV RANGE; GOLD; HARMONICS; KAONS; LEAD; OMEGA BARYONS; PIONS; PROTONS; QUARKS; RELATIVISTIC RANGE; TRANSVERSE MOMENTUM

Citation Formats

Abelev, B. I., Baumgart, S., Bielcik, J., Bielcikova, J., Caines, H., Catu, O., Chikanian, A., Du, F., Finch, E., Harris, J. W., Heinz, M., Knospe, A. G., Lamont, M. A. C., Lin, G., Majka, R., Nattrass, C., Salur, S., Sandweiss, J., Smirnov, N., and Witt, R. Mass, quark-number, and {radical}(s{sub NN}) dependence of the second and fourth flow harmonics in ultrarelativistic nucleus-nucleus collisions. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.054906.
Abelev, B. I., Baumgart, S., Bielcik, J., Bielcikova, J., Caines, H., Catu, O., Chikanian, A., Du, F., Finch, E., Harris, J. W., Heinz, M., Knospe, A. G., Lamont, M. A. C., Lin, G., Majka, R., Nattrass, C., Salur, S., Sandweiss, J., Smirnov, N., & Witt, R. Mass, quark-number, and {radical}(s{sub NN}) dependence of the second and fourth flow harmonics in ultrarelativistic nucleus-nucleus collisions. United States. doi:10.1103/PHYSREVC.75.054906.
Abelev, B. I., Baumgart, S., Bielcik, J., Bielcikova, J., Caines, H., Catu, O., Chikanian, A., Du, F., Finch, E., Harris, J. W., Heinz, M., Knospe, A. G., Lamont, M. A. C., Lin, G., Majka, R., Nattrass, C., Salur, S., Sandweiss, J., Smirnov, N., and Witt, R. Tue . "Mass, quark-number, and {radical}(s{sub NN}) dependence of the second and fourth flow harmonics in ultrarelativistic nucleus-nucleus collisions". United States. doi:10.1103/PHYSREVC.75.054906.
@article{osti_20995310,
title = {Mass, quark-number, and {radical}(s{sub NN}) dependence of the second and fourth flow harmonics in ultrarelativistic nucleus-nucleus collisions},
author = {Abelev, B. I. and Baumgart, S. and Bielcik, J. and Bielcikova, J. and Caines, H. and Catu, O. and Chikanian, A. and Du, F. and Finch, E. and Harris, J. W. and Heinz, M. and Knospe, A. G. and Lamont, M. A. C. and Lin, G. and Majka, R. and Nattrass, C. and Salur, S. and Sandweiss, J. and Smirnov, N. and Witt, R.},
abstractNote = {We present STAR measurements of the azimuthal anisotropy parameter v{sub 2} for pions, kaons, protons, {lambda},{lambda},{xi}+{xi}, and {omega}+{omega}, along with v{sub 4} for pions, kaons, protons, and {lambda}+{lambda} at midrapidity for Au+Au collisions at {radical}(s{sub NN})=62.4 and 200 GeV. The v{sub 2}(p{sub T}) values for all hadron species at 62.4 GeV are similar to those observed in 130 and 200 GeV collisions. For observed kinematic ranges, v{sub 2} values at 62.4, 130, and 200 GeV are as little as 10-15% larger than those in Pb+Pb collisions at {radical}(s{sub NN})=17.3 GeV. At intermediate transverse momentum (p{sub T} from 1.5-5 GeV/c), the 62.4 GeV v{sub 2}(p{sub T}) and v{sub 4}(p{sub T}) values are consistent with the quark-number scaling first observed at 200 GeV. A four-particle cumulant analysis is used to assess the nonflow contributions to pions and protons and some indications are found for a smaller nonflow contribution to protons than pions. Baryon v{sub 2} is larger than antibaryon v{sub 2} at 62.4 and 200 GeV, perhaps indicating either that the initial spatial net-baryon distribution is anisotropic, that the mechanism leading to transport of baryon number from beam- to midrapidity enhances v{sub 2} or that antibaryon and baryon annihilation is larger in the in-plane direction.},
doi = {10.1103/PHYSREVC.75.054906},
journal = {Physical Review. C, Nuclear Physics},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}