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arXiv · 0709.3576

Measuring Quark-Gluon-Plasma Thermalization Time with Dileptons

Mauricio Martinez·Michael Strickland
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Abstract

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_hard(tau), and plasma anisotropy parameter, xi(tau), is constructed which interpolates between free streaming behavior at early times (tau << tau_iso) and ideal hydrodynamic behavior at late times (tau >> tau_iso). We show that high-energy dilepton production is sensitive to the assumed plasma isotropization time, tau_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.

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Mauricio Martinez, Michael Strickland. 2008-03-14. Measuring Quark-Gluon-Plasma Thermalization Time with Dileptons. https://doi.org/10.1103/physrevlett.100.102301

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