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arXiv · 2401.05951

The thermal photon emissivity at the QCD chiral crossover from imaginary momentum correlators

Ardit Krasniqi·Marco Cè·Tim Harris·Renwick J. Hudspith·Harvey B. Meyer·Csaba Török
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Abstract

The thermal photon emissivity at the QCD chiral crossover is investigated using imaginary momentum correlators. These have been measured on a newly generated $20 \times 96^3$ lattice-QCD ensemble with $\mathcal{O}(a)$-improved Wilson quarks and physical up, down and strange quark masses at a temperature $T=154$\,MeV near the pseudo-critical temperature. In order to realize the photon on-shell condition, the spatially transverse Euclidean correlators have to be evaluated at imaginary spatial momenta. Employing a bounding method, we present a preliminary result on the quantity $H_E(ω_1)$, which corresponds to an energy-moment of the photon spectral function $σ(ω)/ω$ defined by the weight function $1/(ω^2+ω_n^2)$, the $ω_n$ being integer multiples of $2πT$.

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Ardit Krasniqi, Marco Cè, Tim Harris, Renwick J. Hudspith, Harvey B. Meyer, Csaba Török. 2024-01-11. The thermal photon emissivity at the QCD chiral crossover from imaginary momentum correlators. https://arxiv.org/abs/2401.05951

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