Constant contribution in meson correlators at finite temperature
Abstract
We discuss a constant contribution to meson correlators at finite temperature. In the deconfinement phase of QCD, a colored single quark state is allowed as a finite energy state, which yields to a contribution of wraparound quark propagation to temporal meson correlators. We investigate the effects in the free quark case and quenched QCD at finite temperature. The 'scattering' contribution causes a constant mode in meson correlators with zero spatial momentum and degenerate quark masses, which can dominate the correlators in the region of large imaginary times. In the free spectral function, the contribution yields a term proportional to {omega}{delta}({omega}). Therefore this contribution is related to transport phenomena in the quark gluon plasma. It is possible to distinguish the constant contribution from the other part using several analysis methods proposed in this paper. As a result of the analyses, we find that drastic changes in charmonium correlators for {chi}{sub c} states just above the deconfinement transition are due to the constant contribution. The other differences in the {chi}{sub c} states are small. It may indicate the survival of {chi}{sub c} states after the deconfinement transition until, at least, 1.4T{sub c}.
 Authors:
 Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
 Publication Date:
 OSTI Identifier:
 21020497
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.75.094502; (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; CHI03415 MESONS; CHI13510 MESONS; CHI23555 MESONS; COLOR MODEL; QUANTUM CHROMODYNAMICS; QUARK MATTER; QUARKS; REST MASS; SPECTRAL FUNCTIONS
Citation Formats
Umeda, Takashi. Constant contribution in meson correlators at finite temperature. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.094502.
Umeda, Takashi. Constant contribution in meson correlators at finite temperature. United States. doi:10.1103/PHYSREVD.75.094502.
Umeda, Takashi. Tue .
"Constant contribution in meson correlators at finite temperature". United States.
doi:10.1103/PHYSREVD.75.094502.
@article{osti_21020497,
title = {Constant contribution in meson correlators at finite temperature},
author = {Umeda, Takashi},
abstractNote = {We discuss a constant contribution to meson correlators at finite temperature. In the deconfinement phase of QCD, a colored single quark state is allowed as a finite energy state, which yields to a contribution of wraparound quark propagation to temporal meson correlators. We investigate the effects in the free quark case and quenched QCD at finite temperature. The 'scattering' contribution causes a constant mode in meson correlators with zero spatial momentum and degenerate quark masses, which can dominate the correlators in the region of large imaginary times. In the free spectral function, the contribution yields a term proportional to {omega}{delta}({omega}). Therefore this contribution is related to transport phenomena in the quark gluon plasma. It is possible to distinguish the constant contribution from the other part using several analysis methods proposed in this paper. As a result of the analyses, we find that drastic changes in charmonium correlators for {chi}{sub c} states just above the deconfinement transition are due to the constant contribution. The other differences in the {chi}{sub c} states are small. It may indicate the survival of {chi}{sub c} states after the deconfinement transition until, at least, 1.4T{sub c}.},
doi = {10.1103/PHYSREVD.75.094502},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}

We study the temperature dependence of the pion decay constant and {rho}meson mass in the hidden local symmetry model at one loop. Using the standard imaginary time formalism, we include the thermal effect of the {rho} meson as well as that of the pion. We show that the pion gives a dominant contribution to the pion decay constant and the {rho}meson contribution slightly decreases the critical temperature. The {rho}meson pole mass increases as T{sup 4}/m{sub {rho}}{sup 2} at low temperature, dominated by the pionloop effect. At high temperature, although the pionloop effect decreases the {rho}meson mass, the {rho}loop contribution overcomesmore »

Current correlators in QCD at finite temperature
Current correlators in QCD at a finite temperature [ital T] are considered from the viewpoint of the operatorproduct expansion. It is stressed that at low [ital T] the heat bath must be represented by hadronic, and not quarkgluon, states. A possibility to express the results in terms of [ital T]dependent resonance masses is discussed. It is demonstrated that to order [ital T][sup 2] the masses do not move and the only phenomenon which occurs is a parity and isospin mixing. 
Comment on ``Current correlators in QCD at finite temperature``
We address some criticisms by Eletsky and Ioffe on the extension of QCD sum rules to finite temperature. We argue that this extension is possible, provided the operator product expansion and QCDhadron duality remain valid at nonzero temperature. We discuss evidence in support of this from QCD, and from the exactly solvable twodimensional {sigma} model O({ital N}) in the large {ital N} limit, and the Schwinger model. 
Reply to ``Comment on `Current correlators in QCD at finite temperature` ``
We insist that, contrary to the statement by Dominguez and Loewe in the preceding Comment, only the hadron basis provides a tractable framework for calculations in QCD at low temperatures, while the quarkgluonbased perturbative treatment is not applicable in this case. 
Topology, fermionic zero modes, and flavor singlet correlators in finite temperature QCD
We compute the screening correlators in the {sigma} and {eta}{sup {prime}} flavor singlet channels in finite temperature QCD with 2 light quark flavors. Together with the correlators in the {rvec {pi}} and {rvec {delta}} channels, these are used to discuss several issues related to symmetry restoration and the nature of the QCD phase transition. Our calculations span a range of temperature extending from approximately 125thinspMeV to 170thinspMeV and are carried out in the context of a staggered fermion formulation on a 16{sup 3}{times}8 lattice. In addition to the computation at a fixed quark mass (am{sub q}=0.00625), we discuss the issuemore »