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Medium effect on photon production in ultrarelativistic nuclear collisions

Chung-sik Song·George Fai
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Abstract

The effect of in-medium vector and axial-vector meson masses on photon production is studied. We assume that the effective mass of a vector meson in hot nuclear matter decreases according to a universal scaling law, while that of an axial-vector meson is given by Weinberg's mass formula. We find that the thermal production rate of photons increases with reduced masses, and is enhanced by an order of magnitude at T=160 MeV with $m_ρ=300$ MeV. Assuming a hydrodynamic evolution, we estimate the effect of the reduced masses on photon production in nucleus-nucleus collisions. The result is compared to experimental data from the WA80/WA98 collaboration.

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Chung-sik Song, George Fai. 1998-02-23. Medium effect on photon production in ultrarelativistic nuclear collisions. https://doi.org/10.1103/physrevc.58.1689

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