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Title: Dihadron Tomography of High-Energy Nuclear Collisions inNext-to-Leading Order Perturbative QCD

Abstract

Back-to-back dihadron spectra in high-energy heavy-ioncollisions are studied within the next-to-leading order (NLO)perturbative QCD parton model with jet quenching incorporated viamodified jet fragmentation functions due to radiative parton energy lossin dense medium. The experimentally observed appearance of back-to-backdihadron sat high p_T is found to originate mainly from jet pairsproduced close and tangential to the surface of the dense matter.However, a substantial fraction of observed high p_T dihadrons also comesfrom jets produced at the center of the medium after losing finite amountof energy. Consequently, the suppression factor of such high-p_T hadronpairs is foundto be more sensitive to the initial gluon density than thesingle hadron spectra that are dominated by surface emission. Asimultaneous chi2-fit to both the single and dihadron spectra can beachieved within an arrow range of the energy loss parametersepsilon_0=1.6-2.1 GeV/fm. Because of the flattening of the initial jetproduction spectra, high p_T dihadrons at the LHC energy are found to bemore robust as probes of the dense medium.

Authors:
; ; ;
Publication Date:
Research Org.:
COLLABORATION - Huazhong NormalU./China
OSTI Identifier:
923204
Report Number(s):
LBNL-62151
Journal ID: ISSN 0031-9007; PRLTAO; R&D Project: NTCOST; BnR: KB0301020; TRN: US0801791
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Related Information: Journal Publication Date: 25 May 2007
Country of Publication:
United States
Language:
English
Subject:
72; FRAGMENTATION; GLUONS; HADRONS; PROBES; PRODUCTION; QUANTUM CHROMODYNAMICS; QUENCHING; SPECTRA; TOMOGRAPHY; Dihadron Dijet Jet quenching QGP

Citation Formats

Zhang, Hanzhong, Owens, Joseph F., Wang, Enke, and Wang, Xin-Nian. Dihadron Tomography of High-Energy Nuclear Collisions inNext-to-Leading Order Perturbative QCD. United States: N. p., 2007. Web. doi:10.1103/PhysRevLett.98.212301.
Zhang, Hanzhong, Owens, Joseph F., Wang, Enke, & Wang, Xin-Nian. Dihadron Tomography of High-Energy Nuclear Collisions inNext-to-Leading Order Perturbative QCD. United States. doi:10.1103/PhysRevLett.98.212301.
Zhang, Hanzhong, Owens, Joseph F., Wang, Enke, and Wang, Xin-Nian. Wed . "Dihadron Tomography of High-Energy Nuclear Collisions inNext-to-Leading Order Perturbative QCD". United States. doi:10.1103/PhysRevLett.98.212301. https://www.osti.gov/servlets/purl/923204.
@article{osti_923204,
title = {Dihadron Tomography of High-Energy Nuclear Collisions inNext-to-Leading Order Perturbative QCD},
author = {Zhang, Hanzhong and Owens, Joseph F. and Wang, Enke and Wang, Xin-Nian},
abstractNote = {Back-to-back dihadron spectra in high-energy heavy-ioncollisions are studied within the next-to-leading order (NLO)perturbative QCD parton model with jet quenching incorporated viamodified jet fragmentation functions due to radiative parton energy lossin dense medium. The experimentally observed appearance of back-to-backdihadron sat high p_T is found to originate mainly from jet pairsproduced close and tangential to the surface of the dense matter.However, a substantial fraction of observed high p_T dihadrons also comesfrom jets produced at the center of the medium after losing finite amountof energy. Consequently, the suppression factor of such high-p_T hadronpairs is foundto be more sensitive to the initial gluon density than thesingle hadron spectra that are dominated by surface emission. Asimultaneous chi2-fit to both the single and dihadron spectra can beachieved within an arrow range of the energy loss parametersepsilon_0=1.6-2.1 GeV/fm. Because of the flattening of the initial jetproduction spectra, high p_T dihadrons at the LHC energy are found to bemore robust as probes of the dense medium.},
doi = {10.1103/PhysRevLett.98.212301},
journal = {Physical Review Letters},
number = ,
volume = 98,
place = {United States},
year = {Wed Jan 17 00:00:00 EST 2007},
month = {Wed Jan 17 00:00:00 EST 2007}
}
  • Dihadron spectra in high-energy heavy-ion collisions are studied within the next-to-leading order perturbative QCD parton model with modified jet fragmentation functions due to jet quenching. High-p{sub T} back-to-back dihadrons are found to originate mainly from jet pairs produced close and tangential to the surface of the dense matter. However, a substantial fraction also comes from jets produced at the center with finite energy loss. Consequently, high-p{sub T} dihadron spectra are found to be more sensitive to the initial gluon density than the single hadron spectra that are more dominated by surface emission. A simultaneous {chi}{sup 2} fit to both themore » single and dihadron spectra can be achieved within a range of the energy loss parameter {epsilon}{sub 0}=1.6-2.1 GeV/fm. Because of the flattening of the initial jet production spectra at {radical}(s)=5.5 TeV, high p{sub T} dihadrons are found to be more robust as probes of the dense medium.« less
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