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arXiv · 2112.00450

Deep inelastic scattering off quark-gluon plasma and its photon emissivity

Marco Cè·Tim Harris·Harvey B. Meyer·Arianna Toniato·Csaba Török
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Abstract

The photon emissivity of quark-gluon plasma probes the interactions in the medium and differs qualitatively between a weakly coupled and a strongly coupled plasma in the soft-photon regime. The photon emissivity is given by the product of kinematic factors and a spectral function associated with the two-point correlator of the electromagnetic current at lightlike kinematics. A certain Euclidean correlator at imaginary spatial momentum can be calculated in lattice QCD and is given by an integral over the relevant spectral function at lightlike kinematics. I present a first exploratory lattice calculation of this correlator. Secondly, I show how Euclidean correlators at imaginary spatial momenta can also be used to probe the regime of deep inelastic scattering off quark-gluon plasma, which reveals its parton distribution function.

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Marco Cè, Tim Harris, Harvey B. Meyer, Arianna Toniato, Csaba Török. 2021-12-01. Deep inelastic scattering off quark-gluon plasma and its photon emissivity. https://arxiv.org/abs/2112.00450

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