Estimation of the photon production rate using imaginary momentum correlators

Abstract

The thermal photon emission rate is determined by the spatially transverse, in-medium spectral function of the electromagnetic current. Accessing the spectral function using Euclidean data is, however, a challenging problem due to the ill-posed nature of inverting the Laplace transform. In this contribution, we present the first results on implementing the proposal of directly computing the analytic continuation of the retarded correlator at fixed, vanishing virtuality of the photon via the calculation of the appropriate Euclidean correlator at imaginary spatial momentum. We employ two dynamical O( )-improved Wilson fermions at a temperature of 250 MeV.

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

“…Photon emissivity at the QCD chiral crossover from imaginary momentum correlators However, in temperature units the 𝐻 𝐸 -quantity near the pseudocritical temperature is in the same ballpark as our result [29,31] 𝐻 𝐸 (𝜔 1 )…”

QCD thermodynamics: an overview of recent progress

“…In Ref. [38] the first results on implementing the proposal of directly computing the analytic continuation of the retarded correlator at fixed, vanishing virtuality of the photon via the calculation of the appropriate Euclidean correlator at imaginary spatial momentum is presented and tested on 𝑁 f = 2 O (𝑎)-improved Wilson fermions configurations at 𝑇 ∼ 250 MeV.…”

Photon and dilepton production rate in the quark-gluon plasma from lattice QCD

“…Photon and dilepton production in the quark-gluon plasma Harvey B. Meyer An alternative way to probe the photon emissivity of the QGP on the lattice is to compute correlation functions at vanishing virtuality, by injecting an imaginary spatial momentum [22,23]. First results have been reported at this conference [24].…”