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arXiv · 2305.10669

Thermal photon production in Gubser inviscid relativistic fluid dynamics

Jean-François Paquet
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Abstract

The Gubser solution to inviscid relativistic fluid dynamics is used to examine the role of transverse expansion on the energy spectrum of photons radiated by quark-gluon plasma. Transverse flow is shown to be a modest effect on the energy spectrum of photons as a whole, despite its large effect on rare high-energy photons produced at low temperatures. An exact expression is derived for the volume of the plasma as a function of its temperature. A simple formula is obtained for the energy spectrum of high-energy thermal photons, which is used to relate the inverse slope $T_{\textrm{eff}}$ of the photon spectrum at energy $E$ to the maximum temperature of the plasma $T_0$, finding $T_{\textrm{eff}} \approx T_0/(1+\frac{5}{2} \frac{T_0}{E})$.

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Jean-François Paquet. 2023-05-18. Thermal photon production in Gubser inviscid relativistic fluid dynamics. https://arxiv.org/abs/2305.10669

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