Holographic vector mesons from spectral functions at finite baryon or isospin density
Abstract
We consider gauge/gravity duality with flavor for the finitetemperature field theory dual of the AdSSchwarzschild black hole background with embedded D7brane probes. In particular, we investigate spectral functions at finite baryon density in the black hole phase. We determine the resonance frequencies corresponding to mesonmass 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 mesonmass 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 firstorder phase transition. Finally we consider an isospin chemical potential and find that the spectral functions display a resonance peak splitting, similar to the isospin mesonmass splitting observed in effective QCD models.
 Authors:
 MaxPlanckInstitut fuer Physik (WernerHeisenbergInstitut), 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 finitetemperature field theory dual of the AdSSchwarzschild black hole background with embedded D7brane probes. In particular, we investigate spectral functions at finite baryon density in the black hole phase. We determine the resonance frequencies corresponding to mesonmass 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 mesonmass 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 firstorder phase transition. Finally we consider an isospin chemical potential and find that the spectral functions display a resonance peak splitting, similar to the isospin mesonmass 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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