Effect of running coupling on photon emission from quark gluon plasma

We discuss the role of running coupling on the thermal photon yield from quark gluon plasma. It is shown that the photon production rate from the partonic phase is considerably enhanced when running coupling is considered with respect to a fixed value. However, we show by explicit evaluation that although this difference survives the space-time evolution the experimental data cannot distinguish between the two once the hard contribution, which is an essential component of photon production mechanism, is added.

Comments: 5 pages, 5 figures, minor changes in the text, submitted to Phys.Rev.C

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