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Title: Predictions for low-p{sub T} and high-p{sub T} hadron spectra in nearly central Pb+Pb collisions at {radical}(s{sub NN})=5.5 TeV tested at {radical}(s{sub NN})=130 and 200 GeV

Abstract

We study the hadron spectra in nearly central A+A collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) in a broad transverse momentum range. We cover the low-p{sub T} spectra using longitudinally boost-invariant hydrodynamics with initial energy and net-baryon number densities from the perturbative QCD (pQCD)+saturation model. Buildup of the transverse flow and sensitivity of the spectra to a single decoupling temperature T{sub dec} are studied. Comparison with RHIC data at {radical}(s{sub NN})=130 and 200 GeV suggests a rather high value T{sub dec}=150 MeV. The high-p{sub T} spectra are computed using factorized pQCD cross sections, nuclear parton distributions, fragmentation functions, and describing partonic energy loss in the quark-gluon plasma by quenching weights. Overall normalization is fixed on the basis of p+p(p) data and the strength of energy loss is determined from RHIC Au+Au data. Uncertainties are discussed. With constraints from RHIC data, we predict the p{sub T} spectra of hadrons in 5% most central Pb+Pb collisions at the LHC energy {radical}(s{sub NN})=5500 GeV. Because of the closed framework for primary production, we can also predict the net-baryon number at midrapidity, as well as the strength of partonic energy losses at the LHC. Both at themore » LHC and RHIC, we recognize a rather narrow crossover region in the p{sub T} spectra, where the hydrodynamic and pQCD fragmentation components become of equal size. We argue that in this crossover region the two contributions are to a good approximation mutually independent. In particular, our results suggest a wider p{sub T} region of applicability for hydrodynamical models at the LHC than at RHIC.« less

Authors:
; ;  [1];  [1];  [1]
  1. Department of Physics, P.B. 35, FIN-40014 University of Jyvaeskylae (Finland)
Publication Date:
OSTI Identifier:
20699080
Resource Type:
Journal Article
Journal Name:
Physical Review. C, Nuclear Physics
Additional Journal Information:
Journal Volume: 72; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevC.72.044904; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0556-2813
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; BARYON NUMBER; BROOKHAVEN RHIC; CERN LHC; COMPARATIVE EVALUATIONS; CROSS SECTIONS; DECOUPLING; DENSITY; ENERGY LOSSES; GEV RANGE; HADRONS; LEAD 208 REACTIONS; LEAD 208 TARGET; NUCLEAR FRAGMENTATION; PARTON MODEL; PARTONS; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS; QUARK MATTER; TEV RANGE; TRANSVERSE MOMENTUM

Citation Formats

Eskola, K J, Niemi, H, Ruuskanen, P V, Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki, Honkanen, H, Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki, Department of Physics, University of Virginia, P.O.B. 400714, Charlottesville, Virginia 22904-4714, and Raesaenen, S S. Predictions for low-p{sub T} and high-p{sub T} hadron spectra in nearly central Pb+Pb collisions at {radical}(s{sub NN})=5.5 TeV tested at {radical}(s{sub NN})=130 and 200 GeV. United States: N. p., 2005. Web. doi:10.1103/PhysRevC.72.044904.
Eskola, K J, Niemi, H, Ruuskanen, P V, Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki, Honkanen, H, Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki, Department of Physics, University of Virginia, P.O.B. 400714, Charlottesville, Virginia 22904-4714, & Raesaenen, S S. Predictions for low-p{sub T} and high-p{sub T} hadron spectra in nearly central Pb+Pb collisions at {radical}(s{sub NN})=5.5 TeV tested at {radical}(s{sub NN})=130 and 200 GeV. United States. https://doi.org/10.1103/PhysRevC.72.044904
Eskola, K J, Niemi, H, Ruuskanen, P V, Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki, Honkanen, H, Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki, Department of Physics, University of Virginia, P.O.B. 400714, Charlottesville, Virginia 22904-4714, and Raesaenen, S S. Sat . "Predictions for low-p{sub T} and high-p{sub T} hadron spectra in nearly central Pb+Pb collisions at {radical}(s{sub NN})=5.5 TeV tested at {radical}(s{sub NN})=130 and 200 GeV". United States. https://doi.org/10.1103/PhysRevC.72.044904.
@article{osti_20699080,
title = {Predictions for low-p{sub T} and high-p{sub T} hadron spectra in nearly central Pb+Pb collisions at {radical}(s{sub NN})=5.5 TeV tested at {radical}(s{sub NN})=130 and 200 GeV},
author = {Eskola, K J and Niemi, H and Ruuskanen, P V and Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki and Honkanen, H and Helsinki Institute of Physics, P.B. 64, FIN-00014 University of Helsinki and Department of Physics, University of Virginia, P.O.B. 400714, Charlottesville, Virginia 22904-4714 and Raesaenen, S S},
abstractNote = {We study the hadron spectra in nearly central A+A collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) in a broad transverse momentum range. We cover the low-p{sub T} spectra using longitudinally boost-invariant hydrodynamics with initial energy and net-baryon number densities from the perturbative QCD (pQCD)+saturation model. Buildup of the transverse flow and sensitivity of the spectra to a single decoupling temperature T{sub dec} are studied. Comparison with RHIC data at {radical}(s{sub NN})=130 and 200 GeV suggests a rather high value T{sub dec}=150 MeV. The high-p{sub T} spectra are computed using factorized pQCD cross sections, nuclear parton distributions, fragmentation functions, and describing partonic energy loss in the quark-gluon plasma by quenching weights. Overall normalization is fixed on the basis of p+p(p) data and the strength of energy loss is determined from RHIC Au+Au data. Uncertainties are discussed. With constraints from RHIC data, we predict the p{sub T} spectra of hadrons in 5% most central Pb+Pb collisions at the LHC energy {radical}(s{sub NN})=5500 GeV. Because of the closed framework for primary production, we can also predict the net-baryon number at midrapidity, as well as the strength of partonic energy losses at the LHC. Both at the LHC and RHIC, we recognize a rather narrow crossover region in the p{sub T} spectra, where the hydrodynamic and pQCD fragmentation components become of equal size. We argue that in this crossover region the two contributions are to a good approximation mutually independent. In particular, our results suggest a wider p{sub T} region of applicability for hydrodynamical models at the LHC than at RHIC.},
doi = {10.1103/PhysRevC.72.044904},
url = {https://www.osti.gov/biblio/20699080}, journal = {Physical Review. C, Nuclear Physics},
issn = {0556-2813},
number = 4,
volume = 72,
place = {United States},
year = {2005},
month = {10}
}