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arXiv · 2505.07169

Enhancement of photon emission rate near QCD critical point

Yukinao Akamatsu·Masayuki Asakawa·Masaru Hongo·Mikhail Stephanov·Ho-Ung Yee
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Abstract

We compute photon emission rate enhancement near the QCD critical point using an effective theory of dynamic critical phenomena and derive a universal photon spectrum. The emission rate scales similarly to conductivity, increasing with the correlation length ($\xi$), diverging at the critical point. The spectrum exhibits $\omega dN_{\gamma}/d^3k \propto \omega^{-1/2}$ in the scaling regime, with the transition occurring at a frequency comparable to shear damping rate $\omega \sim \gamma_{\eta}/\xi^2$, reflecting the nonequilibrium properties of the near-critical liquid.

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Yukinao Akamatsu, Masayuki Asakawa, Masaru Hongo, Mikhail Stephanov, Ho-Ung Yee. 2025-05-12. Enhancement of photon emission rate near QCD critical point. https://doi.org/10.1103/d6nz-ctrc

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