skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Rapidity and centrality dependence of particle production for identified hadrons in Cu + Cu collisions at s NN = 200 GeV

Abstract

The BRAHMS collaboration has measured transverse momentum spectra of pions, kaons, protons, and antiprotons at rapidities 0 and 3 for Cu+Cu collisions at s NN = 200 GeV. As the collisions become more central the collective radial flow increases while the temperature of kinetic freeze-out decreases. The temperature is lower and the radial flow weaker at forward rapidity. Pion and kaon yields with transverse momenta between 1.5 and 2.5 GeV/c are suppressed for central collisions relative to scaled p + p collisions. This suppression, which increases as the collisions become more central, is consistent with jet quenching models and is also present with comparable magnitude at forward rapidity. At such rapidities, initial state effects may also be present and persistence of the meson suppression to high rapidity may reflect a combination of jet quenching and nuclear shadowing. In conclusion, the ratio of protons to mesons increases as the collisions become more central and is largest at forward rapidities.

Authors:
 [1]
  1. Univ. of Oslo (Norway). Department of Physics. et al.
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States). Relativistic Heavy Ion Collider (RHIC)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1340370
Report Number(s):
BNL-112479-2016-JA
Journal ID: ISSN 2469-9985; R&D Project: PO 004; KB0202012; TRN: US1701777
Grant/Contract Number:
SC00112704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review C
Additional Journal Information:
Journal Volume: 94; Journal Issue: 1; Journal ID: ISSN 2469-9985
Publisher:
APS
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Relativistic Heavy Ion Collider

Citation Formats

Arsene, I. C.. Rapidity and centrality dependence of particle production for identified hadrons in Cu + Cu collisions at sNN=200 GeV. United States: N. p., 2016. Web. doi:10.1103/PhysRevC.94.014907.
Arsene, I. C.. Rapidity and centrality dependence of particle production for identified hadrons in Cu + Cu collisions at sNN=200 GeV. United States. doi:10.1103/PhysRevC.94.014907.
Arsene, I. C.. 2016. "Rapidity and centrality dependence of particle production for identified hadrons in Cu + Cu collisions at sNN=200 GeV". United States. doi:10.1103/PhysRevC.94.014907. https://www.osti.gov/servlets/purl/1340370.
@article{osti_1340370,
title = {Rapidity and centrality dependence of particle production for identified hadrons in Cu + Cu collisions at sNN=200 GeV},
author = {Arsene, I. C.},
abstractNote = {The BRAHMS collaboration has measured transverse momentum spectra of pions, kaons, protons, and antiprotons at rapidities 0 and 3 for Cu+Cu collisions at sNN=200 GeV. As the collisions become more central the collective radial flow increases while the temperature of kinetic freeze-out decreases. The temperature is lower and the radial flow weaker at forward rapidity. Pion and kaon yields with transverse momenta between 1.5 and 2.5 GeV/c are suppressed for central collisions relative to scaled p + p collisions. This suppression, which increases as the collisions become more central, is consistent with jet quenching models and is also present with comparable magnitude at forward rapidity. At such rapidities, initial state effects may also be present and persistence of the meson suppression to high rapidity may reflect a combination of jet quenching and nuclear shadowing. In conclusion, the ratio of protons to mesons increases as the collisions become more central and is largest at forward rapidities.},
doi = {10.1103/PhysRevC.94.014907},
journal = {Physical Review C},
number = 1,
volume = 94,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share:
  • © 2015 CERN for the benefit of the ATLAS Collaboration. Measurements of the centrality and rapidity dependence of inclusive jet production in sNN=5.02 TeV proton-lead (p+Pb) collisions and the jet cross-section in s=2.76 TeV proton-proton collisions are presented. These quantities are measured in datasets corresponding to an integrated luminosity of 27.8 nb < sup > -1 < /sup > and 4.0 pb < sup > -1 < /sup > , respectively, recorded with the ATLAS detector at the Large Hadron Collider in 2013. The p+Pb collision centrality was characterised using the total transverse energy measured in the pseudorapidity interval -4.9more » < η < -3.2 in the direction of the lead beam. Results are presented for the double-differential per-collision yields as a function of jet rapidity and transverse momentum (p < inf > T < /inf > ) for minimum-bias and centrality-selected p+Pb collisions, and are compared to the jet rate from the geometric expectation. The total jet yield in minimum-bias events is slightly enhanced above the expectation in a p < inf > T < /inf > -dependent manner but is consistent with the expectation within uncertainties. The ratios of jet spectra from different centrality selections show a strong modification of jet production at all p < inf > T < /inf > at forward rapidities and for large p < inf > T < /inf > at mid-rapidity, which manifests as a suppression of the jet yield in central events and an enhancement in peripheral events. These effects imply that the factorisation between hard and soft processes is violated at an unexpected level in proton-nucleus collisions. Furthermore, the modifications at forward rapidities are found to be a function of the total jet energy only, implying that the violations may have a simple dependence on the hard parton-parton kinematics.« less
  • The first study of Φ -meson production in p–Pb collisions at forward and backward rapidity, at a nucleon–nucleon centre-of-mass energy View the MathML source, has been performed with the ALICE apparatus at the LHC. The Φ -mesons have been identified in the dimuon decay channel in the transverse momentum (p T) range 1 < p T <7 GeV/c, both in the p-going (2.03 < y < 3.53) and the Pb-going (-4.46 < y < -2.96) directions — where y stands for the rapidity in the nucleon–nucleon centre-of-mass — the integrated luminosity amounting to 5.01±0.19 nb -1 and 5.81±0.20 nb -1, respectively, for the two data samples. Differential cross sections as a function of transverse momentum and rapidity are presented. The forward–backward ratio for Φ -meson production is measured for 2.96<|y|<3.53, resulting in a ratio ~0.5 with no significant pT dependence within the uncertainties. The pT dependence of the Φ nuclear modification factor RpPb exhibits an enhancement up to a factor 1.6 at pT=3–4 GeV/c in the Pb-going direction. The pT dependence of the Φ -meson cross section in pp collisions atmore » $$\sqrt{s}$$ = 2.76, which is used to determine a reference for the p–Pb results, is also presented here for 1< p T <5 GeV/c and 2.5 < y < 4, for a 78±3 nb -1 integrated luminosity sample.« less
  • The first study of Φ -meson production in p–Pb collisions at forward and backward rapidity, at a nucleon–nucleon centre-of-mass energy View the MathML source, has been performed with the ALICE apparatus at the LHC. The Φ -mesons have been identified in the dimuon decay channel in the transverse momentum (p T) range 1 < p T <7 GeV/c, both in the p-going (2.03 < y < 3.53) and the Pb-going (-4.46 < y < -2.96) directions — where y stands for the rapidity in the nucleon–nucleon centre-of-mass — the integrated luminosity amounting to 5.01±0.19 nb -1 and 5.81±0.20 nb -1, respectively, for the two data samples. Differential cross sections as a function of transverse momentum and rapidity are presented. The forward–backward ratio for Φ -meson production is measured for 2.96<|y|<3.53, resulting in a ratio ~0.5 with no significant pT dependence within the uncertainties. The pT dependence of the Φ nuclear modification factor RpPb exhibits an enhancement up to a factor 1.6 at pT=3–4 GeV/c in the Pb-going direction. The pT dependence of the Φ -meson cross section in pp collisions atmore » $$\sqrt{s}$$ = 2.76, which is used to determine a reference for the p–Pb results, is also presented here for 1< p T <5 GeV/c and 2.5 < y < 4, for a 78±3 nb -1 integrated luminosity sample.« less
  • The first study ofmore » $$\phi$$-meson production in p–Pb collisions at forward and backward rapidity, at a nucleon–nucleon centre-of-mass energy s NN =5.02 TeV, has been performed with the ALICE apparatus at the LHC. The $$\phi$$-mesons have been identified in the dimuon decay channel in the transverse momentum (p T ) range 1 < p T < 7 GeV/c, both in the p-going (2.03 < y < 3.53) and the Pb-going (-4.46 < y < -2.96) directions — where y stands for the rapidity in the nucleon–nucleon centre-of-mass — the integrated luminosity amounting to 5.01±0.19 nb-1 and 5.81±0.20 nb-1 , respectively, for the two data samples. Differential cross sections as a function of transverse momentum and rapidity are presented. The forward–backward ratio for $$\phi$$-meson production is measured for 2.96 < |y| < 3.53, resulting in a ratio ~0.5 with no significant p T dependence within the uncertainties. The p T dependence of the $$\phi$$ nuclear modification factor R pPb exhibits an enhancement up to a factor 1.6 at p T =3–4 GeV/c in the Pb-going direction. The p T dependence of the $$\phi$$-meson cross section in pp collisions at s=2.76 TeV, which is used to determine a reference for the p–Pb results, is also presented here for 1 < p T < 5 GeV/c and 2.5 < y < 4, for a 78±3 nb-1 integrated luminosity sample.« less