Measuring Quark-Gluon-Plasma Thermalization Time with Dileptons

Journal Article · Fri Mar 14 04:00:00 EDT 2008 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.100.102301· OSTI ID:21123732

Martinez, Mauricio ^[1]; Strickland, Michael ^[2]

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1. Helmholtz Research School, Johann Wolfgang Goethe-Universitaet Frankfurt, Ruth-Moufang-Strasse 1, D-60438 Frankfurt am Main (Germany)
2. Institut fuer Theoretische Physik and Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe-Universitaet Frankfurt, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main (Germany)

We calculate the medium dilepton yield from a quark-gluon plasma which has a time-dependent local momentum-space anisotropy. A phenomenological model for the hard momentum scale, p{sub hard}({tau}), and plasma anisotropy parameter, {xi}({tau}), is constructed which interpolates between longitudinal free streaming at early times ({tau}<<{tau}{sub iso}) and ideal hydrodynamic at late times ({tau}>>{tau}{sub iso}). We show that high-energy dilepton production is sensitive to the plasma isotropization time, {tau}{sub iso}, and can therefore be used to experimentally determine the time of onset for hydrodynamic expansion of a quark-gluon plasma and the magnitude of expected early-time momentum-space anisotropies.

• OSTI ID: 21123732
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 10 Vol. 100; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANISOTROPY
PLASMA
QUARK MATTER
THERMALIZATION
TIME DEPENDENCE