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arXiv · 1710.07050

An estimate for the thermal photon rate from lattice QCD

Bastian B. Brandt·Anthony Francis·Tim Harris·Harvey B. Meyer·Aman Steinberg
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Abstract

We estimate the production rate of photons by the quark-gluon plasma in lattice QCD. We propose a new correlation function which provides better control over the systematic uncertainty in estimating the photon production rate at photon momenta in the range {\pi}T/2 to 2{\pi}T. The relevant Euclidean vector current correlation functions are computed with $N_{\mathrm f}$ = 2 Wilson clover fermions in the chirally-symmetric phase. In order to estimate the photon rate, an ill-posed problem for the vector-channel spectral function must be regularized. We use both a direct model for the spectral function and a model-independent estimate from the Backus-Gilbert method to give an estimate for the photon rate.

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Bastian B. Brandt, Anthony Francis, Tim Harris, Harvey B. Meyer, Aman Steinberg. 2017-10-19. An estimate for the thermal photon rate from lattice QCD. https://doi.org/10.1051/epjconf/201817507044

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