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Title: Holographic vector mesons from spectral functions at finite baryon or isospin density

Abstract

We consider gauge/gravity duality with flavor for the finite-temperature field theory dual of the AdS-Schwarzschild black hole background with embedded D7-brane probes. In particular, we investigate spectral functions at finite baryon density in the black hole phase. We determine the resonance frequencies corresponding to meson-mass peaks as function of the quark mass over temperature ratio. We find that these frequencies have a minimum for a finite value of the quark mass. If the quotient of quark mass and temperature is increased further, the peaks move to larger frequencies. At the same time the peaks narrow, in agreement with the formation of nearly stable vector meson states which exactly reproduce the meson-mass spectrum found at zero temperature. We also calculate the diffusion coefficient, which has finite value for all quark mass to temperature ratios, and exhibits a first-order phase transition. Finally we consider an isospin chemical potential and find that the spectral functions display a resonance peak splitting, similar to the isospin meson-mass splitting observed in effective QCD models.

Authors:
; ;  [1]
  1. Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Munich (Germany)
Publication Date:
OSTI Identifier:
21039204
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 77; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.77.046005; (c) 2008 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; BARYONS; BLACK HOLES; DUALITY; FLAVOR MODEL; GRAVITATION; HOLOGRAPHY; ISOSPIN; MASS SPECTRA; PHASE TRANSFORMATIONS; POTENTIALS; QUANTUM CHROMODYNAMICS; QUARKS; REST MASS; SPECTRAL FUNCTIONS; VECTOR MESONS

Citation Formats

Erdmenger, Johanna, Kaminski, Matthias, and Rust, Felix. Holographic vector mesons from spectral functions at finite baryon or isospin density. United States: N. p., 2008. Web. doi:10.1103/PHYSREVD.77.046005.
Erdmenger, Johanna, Kaminski, Matthias, & Rust, Felix. Holographic vector mesons from spectral functions at finite baryon or isospin density. United States. doi:10.1103/PHYSREVD.77.046005.
Erdmenger, Johanna, Kaminski, Matthias, and Rust, Felix. Fri . "Holographic vector mesons from spectral functions at finite baryon or isospin density". United States. doi:10.1103/PHYSREVD.77.046005.
@article{osti_21039204,
title = {Holographic vector mesons from spectral functions at finite baryon or isospin density},
author = {Erdmenger, Johanna and Kaminski, Matthias and Rust, Felix},
abstractNote = {We consider gauge/gravity duality with flavor for the finite-temperature field theory dual of the AdS-Schwarzschild black hole background with embedded D7-brane probes. In particular, we investigate spectral functions at finite baryon density in the black hole phase. We determine the resonance frequencies corresponding to meson-mass peaks as function of the quark mass over temperature ratio. We find that these frequencies have a minimum for a finite value of the quark mass. If the quotient of quark mass and temperature is increased further, the peaks move to larger frequencies. At the same time the peaks narrow, in agreement with the formation of nearly stable vector meson states which exactly reproduce the meson-mass spectrum found at zero temperature. We also calculate the diffusion coefficient, which has finite value for all quark mass to temperature ratios, and exhibits a first-order phase transition. Finally we consider an isospin chemical potential and find that the spectral functions display a resonance peak splitting, similar to the isospin meson-mass splitting observed in effective QCD models.},
doi = {10.1103/PHYSREVD.77.046005},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 77,
place = {United States},
year = {Fri Feb 15 00:00:00 EST 2008},
month = {Fri Feb 15 00:00:00 EST 2008}
}
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