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Title: Quark number scaling of v{sub 2} in transverse kinetic energy and its implications for coalescence models

Abstract

We find that a simple extension of the coalescence model is sufficient to incorporate the perfect quark number scaling behavior of the elliptic flow in transverse kinetic energy, recently discovered by the PHENIX Collaboration. The flavor dependence of the elliptic flow can be consistently described in the low and intermediate p{sub T} if the transverse kinetic energy is conserved in the 2{yields}1 or 3{yields}1 parton coalescence process at the hadronization. Thus suggesting the quark coalescence as a possible hadronization mechanism at low p{sub T} as well.

Authors:
 [1];  [2];  [3]
  1. Columbia University, New York, New York 10027 and Nevis Laboratories, Irvington, New York 10533 (United States)
  2. (United States)
  3. Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)
Publication Date:
OSTI Identifier:
20995107
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevC.75.031901; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COALESCENCE; HADRONS; KINETIC ENERGY; QUARKS; SCALING

Citation Formats

Jia Jiangyong, Department of Chemistry, Stony Brook University, Stony Brook, New York 11794, and Zhang Chun. Quark number scaling of v{sub 2} in transverse kinetic energy and its implications for coalescence models. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.031901.
Jia Jiangyong, Department of Chemistry, Stony Brook University, Stony Brook, New York 11794, & Zhang Chun. Quark number scaling of v{sub 2} in transverse kinetic energy and its implications for coalescence models. United States. doi:10.1103/PHYSREVC.75.031901.
Jia Jiangyong, Department of Chemistry, Stony Brook University, Stony Brook, New York 11794, and Zhang Chun. Thu . "Quark number scaling of v{sub 2} in transverse kinetic energy and its implications for coalescence models". United States. doi:10.1103/PHYSREVC.75.031901.
@article{osti_20995107,
title = {Quark number scaling of v{sub 2} in transverse kinetic energy and its implications for coalescence models},
author = {Jia Jiangyong and Department of Chemistry, Stony Brook University, Stony Brook, New York 11794 and Zhang Chun},
abstractNote = {We find that a simple extension of the coalescence model is sufficient to incorporate the perfect quark number scaling behavior of the elliptic flow in transverse kinetic energy, recently discovered by the PHENIX Collaboration. The flavor dependence of the elliptic flow can be consistently described in the low and intermediate p{sub T} if the transverse kinetic energy is conserved in the 2{yields}1 or 3{yields}1 parton coalescence process at the hadronization. Thus suggesting the quark coalescence as a possible hadronization mechanism at low p{sub T} as well.},
doi = {10.1103/PHYSREVC.75.031901},
journal = {Physical Review. C, Nuclear Physics},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
  • We find that a simple extension of the coalescence model is sufficient to incorporate the perfect quark number scaling behavior of the elliptic flow in transverse kinetic energy, recently discovered by the PHENIX Collaboration. The flavor dependence of the elliptic flow can be consistently described in the low and intermediate p{sub T} if the transverse kinetic energy is conserved in the 2 {yields} 1 or 3 {yields} 1 parton coalescence process at the hadronization. Thus suggesting the quark coalescence as a possible hadronization mechanism at low p{sub T} as well.
  • Measurements of the anisotropy parameter v{sub 2} of identified hadrons (pions, kaons, and protons) as a function of centrality, transverse momentum p{sub T}, and transverse kinetic energy KE{sub T} at midrapidity (|{eta}| < 0.35) in Au + Au collisions at {radical}s{sub NN} = 200 GeV are presented. Pions and protons are identified up to p{sub T} = 6 GeV/c, and kaons up to p{sub T} = 4 GeV/c, by combining information from time-of-flight and aerogel Cerenkov detectors in the PHENIX Experiment. The scaling of v{sub 2} with the number of valence quarks (n{sub q}) has been studied in different centralitymore » bins as a function of transverse momentum and transverse kinetic energy. A deviation from previously observed quark-number scaling is observed at large values of KE{sub T}/n{sub q} in noncentral Au + Au collisions (20-60%), but this scaling remains valid in central collisions (0-10%).« less
  • An updated measurement of the single top quark production cross section is presented using the full data set collected by the Collider Detector at Fermilab (CDF), corresponding to 9.5 fb -1 of integrated luminosity from proton-antiproton collisions at 1.96 TeV center-of-mass energy. The events selected contain an imbalance in the total transverse momentum, jets identified as containing b quarks, and no identified leptons. The sum of the s- and t-channel single top quark cross sections is measured to be 3.53 -1.16 +1.25 pb and a lower limit on the magnitude of the top-to-bottom quark coupling, |V tb| of 0.63, is obtainedmore » at the 95% credibility level. These measurements are combined with previously reported CDF results obtained from events with an imbalance in total transverse momentum, jets identified as originating from b quarks, and one identified lepton. Furthermore, the combined cross section is measured to be 3.02 -0.48 +0.49 pb and a lower limit on |V tb| of 0.84 is obtained at the 95% credibility level.« less
    Cited by 2
  • An updated measurement of the single top quark production cross section is presented using the full data set collected by the Collider Detector at Fermilab (CDF), corresponding to 9.5 fb -1 of integrated luminosity from proton-antiproton collisions at 1.96 TeV center-of-mass energy. The events selected contain an imbalance in the total transverse momentum, jets identified as containing b quarks, and no identified leptons. The sum of the s- and t-channel single top quark cross sections is measured to be 3.53 -1.16 +1.25 pb and a lower limit on the magnitude of the top-to-bottom quark coupling, |V tb| of 0.63, is obtainedmore » at the 95% credibility level. These measurements are combined with previously reported CDF results obtained from events with an imbalance in total transverse momentum, jets identified as originating from b quarks, and one identified lepton. Furthermore, the combined cross section is measured to be 3.02 -0.48 +0.49 pb and a lower limit on |V tb| of 0.84 is obtained at the 95% credibility level.« less