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arXiv · 0808.3969

Suppression of forward dilepton production from an anisotropic quark-gluon plasma

Mauricio Martinez·Michael Strickland
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Abstract

We calculate the rapidity dependence of leading-order medium dilepton yields resulting from a quark-gluon plasma which has a local time-dependent anisotropy in momentum space. We present a phenomenological model which includes temporal evolution of the plasma anisotropy parameter, xi, and the hard momentum scale, p_hard. Our model interpolates between 1+1 dimensional collisionally-broadened expansion at early times and 1+1 dimensional ideal hydrodynamic expansion at late times. Using our model, we find that at LHC energies, forward high-energy medium dilepton production would be suppressed by up to a factor of 3 if one assumes an isotropization/thermalization time of 2 fm/c. Therefore, it may be possible to use forward dilepton yields to experimentally determine the time of onset of locally isotropic hydrodynamic expansion of the quark-gluon plasma as produced in ultrarelativistic heavy-ion collisions.

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Mauricio Martinez, Michael Strickland. 2008-08-28. Suppression of forward dilepton production from an anisotropic quark-gluon plasma. https://doi.org/10.1140/epjc%2Fs10052-008-0851-8

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