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arXiv · 1912.00292

Lattice QCD estimate of the quark-gluon plasma photon emission rate

Bastian B. Brandt·Marco Cè·Anthony Francis·Tim Harris·Harvey B. Meyer·Aman Steinberg·Arianna Toniato
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Abstract

We present a computation of the photon emission rate of the quark-gluon plasma from two-flavor lattice QCD at a temperature of 254 MeV, which follows up on the work presented in [1]. We perform a continuum extrapolation of the vector-current correlator, and consider a linear combination of the Lorentz indices corresponding to a UV-finite spectral function. To extract the spectral function from the lattice correlators, an ill-posed inverse problem, we model the spectral function with a Pad\'e ansatz. We further constrain our analysis by simultaneously fitting data with different momenta. We present results for a multi-momentum fit including the three smallest momenta available from our lattice analysis.

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Bastian B. Brandt, Marco Cè, Anthony Francis, Tim Harris, Harvey B. Meyer, Aman Steinberg, Arianna Toniato. 2019-12-01. Lattice QCD estimate of the quark-gluon plasma photon emission rate. https://arxiv.org/abs/1912.00292

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