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arXiv · 1707.08602

Phenomenology of collinear photon emission from quark-gluon plasma in $AA$ collisions

B. G. Zakharov
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Abstract

We study the role of running coupling and the effect of variation of the thermal quark mass on contribution of the collinear bremsstrahlung and annihilation to photon emission in $AA$ collisions in a scheme similar to that used in our previous jet quenching analyses. We find that for a scenario with the thermal quark mass $m_q\sim 50-100$ MeV contribution of the higher order collinear processes summed with the $2\to 2$ processes can explain a considerable part ($\sim 50$\%) of the experimental photon spectrum at $k_T\sim 2-3$ GeV for Au+Au collisions at $\sqrt{s}=0.2$ TeV. But for $m_q=300$ MeV and for the thermal quark mass predicted by the HTL scheme the theoretical predictions underestimate considerably the experimental spectrum.

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B. G. Zakharov. 2017-07-26. Phenomenology of collinear photon emission from quark-gluon plasma in $AA$ collisions. https://doi.org/10.1134/s0021364017170027

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