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Title: Charged and strange hadron elliptic flow in Cu+Cu collisions at sq root(s{sub NN})=62.4 and 200 GeV

Abstract

We present the results of an elliptic flow, v{sub 2}, analysis of Cu+Cu collisions recorded with the solenoidal tracker detector (STAR) at the BNL Relativistic Heavy Ion Collider at sq root(s{sub NN})=62.4 and 200 GeV. Elliptic flow as a function of transverse momentum, v{sub 2}(p{sub T}), is reported for different collision centralities for charged hadrons h{sup +}- and strangeness-ontaining hadrons K{sub S}{sup 0}, LAMBDA, XI, and phi in the midrapidity region |eta|<1.0. Significant reduction in systematic uncertainty of the measurement due to nonflow effects has been achieved by correlating particles at midrapidity, |eta|<1.0, with those at forward rapidity, 2.5<|eta|<4.0. We also present azimuthal correlations in p+p collisions at sq root(s)=200 GeV to help in estimating nonflow effects. To study the system-size dependence of elliptic flow, we present a detailed comparison with previously published results from Au+Au collisions at sq root(s{sub NN})=200 GeV. We observe that v{sub 2}(p{sub T}) of strange hadrons has similar scaling properties as were first observed in Au+Au collisions, that is, (i) at low transverse momenta, p{sub T}<2 GeV/c, v{sub 2} scales with transverse kinetic energy, m{sub T}-m, and (ii) at intermediate p{sub T}, 2<p{sub T}<4 GeV/c, it scales with the number of constituent quarks, n{sub q}.more » We have found that ideal hydrodynamic calculations fail to reproduce the centrality dependence of v{sub 2}(p{sub T}) for K{sub S}{sup 0} and LAMBDA. Eccentricity scaled v{sub 2} values, v{sub 2}/epsilon, are larger in more central collisions, suggesting stronger collective flow develops in more central collisions. The comparison with Au+Au collisions, which go further in density, shows that v{sub 2}/epsilon depends on the system size, that is, the number of participants N{sub part}. This indicates that the ideal hydrodynamic limit is not reached in Cu+Cu collisions, presumably because the assumption of thermalization is not attained.« less

Authors:
; ; ; ; ; ; ; ;  [1]; ; ; ;  [2]; ; ; ; ; ; ;  [3]
  1. University of Illinois at Chicago, Chicago, Illinois 60607 (United States)
  2. Panjab University, Chandigarh 160014 (India)
  3. Variable Energy Cyclotron Centre, Kolkata 700064 (India)
Publication Date:
OSTI Identifier:
21388953
Resource Type:
Journal Article
Journal Name:
Physical Review. C, Nuclear Physics
Additional Journal Information:
Journal Volume: 81; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevC.81.044902; (c) 2010 The American Physical Society; Journal ID: ISSN 0556-2813
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ATOM-ATOM COLLISIONS; BNL; BROOKHAVEN RHIC; COLLISIONS; COMPARATIVE EVALUATIONS; COPPER; CORRELATIONS; DENSITY; GEV RANGE; GOLD; HYDRODYNAMIC MODEL; KAONS NEUTRAL SHORT-LIVED; KINETIC ENERGY; PARTICLE RAPIDITY; PROTON-PROTON INTERACTIONS; QUARKS; SCALING; STRANGENESS; THERMALIZATION; TRANSVERSE MOMENTUM; ACCELERATORS; ATOM COLLISIONS; BARYON-BARYON INTERACTIONS; BOSONS; ELEMENTARY PARTICLES; ELEMENTS; ENERGY; ENERGY RANGE; EVALUATION; FERMIONS; HADRON-HADRON INTERACTIONS; HADRONS; HEAVY ION ACCELERATORS; INTERACTIONS; KAONS; KAONS NEUTRAL; LINEAR MOMENTUM; MATHEMATICAL MODELS; MESONS; METALS; NATIONAL ORGANIZATIONS; NUCLEON-NUCLEON INTERACTIONS; PARTICLE INTERACTIONS; PARTICLE MODELS; PARTICLE PROPERTIES; PHYSICAL PROPERTIES; PROTON-NUCLEON INTERACTIONS; PSEUDOSCALAR MESONS; SLOWING-DOWN; STATISTICAL MODELS; STORAGE RINGS; STRANGE MESONS; STRANGE PARTICLES; THERMODYNAMIC MODEL; TRANSITION ELEMENTS; US AEC; US DOE; US ERDA; US ORGANIZATIONS

Citation Formats

Abelev, B I, Betts, R R, Evdokimov, O, Garcia-Solis, E J, Hofman, D J, Hollis, R S, Iordanova, A, Kauder, K, Suarez, M C, Aggarwal, M M, Bhati, A K, Kumar, L, Pruthi, N K, Ahammed, Z, Chattopadhyay, S, Dutta Mazumdar, M R, Ganti, M S, Ghosh, P, Mohanty, B, and Mondal, M M. Charged and strange hadron elliptic flow in Cu+Cu collisions at sq root(s{sub NN})=62.4 and 200 GeV. United States: N. p., 2010. Web. doi:10.1103/PHYSREVC.81.044902.
Abelev, B I, Betts, R R, Evdokimov, O, Garcia-Solis, E J, Hofman, D J, Hollis, R S, Iordanova, A, Kauder, K, Suarez, M C, Aggarwal, M M, Bhati, A K, Kumar, L, Pruthi, N K, Ahammed, Z, Chattopadhyay, S, Dutta Mazumdar, M R, Ganti, M S, Ghosh, P, Mohanty, B, & Mondal, M M. Charged and strange hadron elliptic flow in Cu+Cu collisions at sq root(s{sub NN})=62.4 and 200 GeV. United States. https://doi.org/10.1103/PHYSREVC.81.044902
Abelev, B I, Betts, R R, Evdokimov, O, Garcia-Solis, E J, Hofman, D J, Hollis, R S, Iordanova, A, Kauder, K, Suarez, M C, Aggarwal, M M, Bhati, A K, Kumar, L, Pruthi, N K, Ahammed, Z, Chattopadhyay, S, Dutta Mazumdar, M R, Ganti, M S, Ghosh, P, Mohanty, B, and Mondal, M M. Thu . "Charged and strange hadron elliptic flow in Cu+Cu collisions at sq root(s{sub NN})=62.4 and 200 GeV". United States. https://doi.org/10.1103/PHYSREVC.81.044902.
@article{osti_21388953,
title = {Charged and strange hadron elliptic flow in Cu+Cu collisions at sq root(s{sub NN})=62.4 and 200 GeV},
author = {Abelev, B I and Betts, R R and Evdokimov, O and Garcia-Solis, E J and Hofman, D J and Hollis, R S and Iordanova, A and Kauder, K and Suarez, M C and Aggarwal, M M and Bhati, A K and Kumar, L and Pruthi, N K and Ahammed, Z and Chattopadhyay, S and Dutta Mazumdar, M R and Ganti, M S and Ghosh, P and Mohanty, B and Mondal, M M},
abstractNote = {We present the results of an elliptic flow, v{sub 2}, analysis of Cu+Cu collisions recorded with the solenoidal tracker detector (STAR) at the BNL Relativistic Heavy Ion Collider at sq root(s{sub NN})=62.4 and 200 GeV. Elliptic flow as a function of transverse momentum, v{sub 2}(p{sub T}), is reported for different collision centralities for charged hadrons h{sup +}- and strangeness-ontaining hadrons K{sub S}{sup 0}, LAMBDA, XI, and phi in the midrapidity region |eta|<1.0. Significant reduction in systematic uncertainty of the measurement due to nonflow effects has been achieved by correlating particles at midrapidity, |eta|<1.0, with those at forward rapidity, 2.5<|eta|<4.0. We also present azimuthal correlations in p+p collisions at sq root(s)=200 GeV to help in estimating nonflow effects. To study the system-size dependence of elliptic flow, we present a detailed comparison with previously published results from Au+Au collisions at sq root(s{sub NN})=200 GeV. We observe that v{sub 2}(p{sub T}) of strange hadrons has similar scaling properties as were first observed in Au+Au collisions, that is, (i) at low transverse momenta, p{sub T}<2 GeV/c, v{sub 2} scales with transverse kinetic energy, m{sub T}-m, and (ii) at intermediate p{sub T}, 2<p{sub T}<4 GeV/c, it scales with the number of constituent quarks, n{sub q}. We have found that ideal hydrodynamic calculations fail to reproduce the centrality dependence of v{sub 2}(p{sub T}) for K{sub S}{sup 0} and LAMBDA. Eccentricity scaled v{sub 2} values, v{sub 2}/epsilon, are larger in more central collisions, suggesting stronger collective flow develops in more central collisions. The comparison with Au+Au collisions, which go further in density, shows that v{sub 2}/epsilon depends on the system size, that is, the number of participants N{sub part}. This indicates that the ideal hydrodynamic limit is not reached in Cu+Cu collisions, presumably because the assumption of thermalization is not attained.},
doi = {10.1103/PHYSREVC.81.044902},
url = {https://www.osti.gov/biblio/21388953}, journal = {Physical Review. C, Nuclear Physics},
issn = {0556-2813},
number = 4,
volume = 81,
place = {United States},
year = {2010},
month = {4}
}