TY - JOUR

T1 - Photon production rate from Transverse-Longitudinal (T - L) mesonic correlator on the lattice

AU - Bala, D.

AU - Ali, S.

AU - Francis, A.

AU - Jackson, G.

AU - Kaczmarek, O.

AU - Ueding, T.

N1 - Publisher Copyright:
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).

PY - 2023/4/6

Y1 - 2023/4/6

N2 - Thermal photons from the QGP provide important information about the interaction among plasma constituents. The photon production rate from a thermally equilibrated system is proportional to the transverse spectral function ρT (ω = |(Equation presented)|, (Equation presented)). One can also calculate the photon production rate from the difference between ρT (ω, (Equation presented)) (transverse) and ρL (ω, (Equation presented)) (longitudinal) projections, as ρL vanishes on the photon point. Because the UV part of ρT - ρL is suppressed, the corresponding Euclidean correlator receives most of its contribution from the IR part. We calculate the T - L correlator on Nf = 2 + 1 flavour HISQ configurations with ml = ms/5 at temperature of about 1.15 Tpc (220 MeV). We have used two ansätze for the spectral function: 1) A polynomial connected to the UV region consistent with OPE expansion and 2) a hydro-inspired spectral function. We have also applied the Backus-Gilbert method to estimate the spectral function. All these different approaches are combined to estimate the photon production rate.

AB - Thermal photons from the QGP provide important information about the interaction among plasma constituents. The photon production rate from a thermally equilibrated system is proportional to the transverse spectral function ρT (ω = |(Equation presented)|, (Equation presented)). One can also calculate the photon production rate from the difference between ρT (ω, (Equation presented)) (transverse) and ρL (ω, (Equation presented)) (longitudinal) projections, as ρL vanishes on the photon point. Because the UV part of ρT - ρL is suppressed, the corresponding Euclidean correlator receives most of its contribution from the IR part. We calculate the T - L correlator on Nf = 2 + 1 flavour HISQ configurations with ml = ms/5 at temperature of about 1.15 Tpc (220 MeV). We have used two ansätze for the spectral function: 1) A polynomial connected to the UV region consistent with OPE expansion and 2) a hydro-inspired spectral function. We have also applied the Backus-Gilbert method to estimate the spectral function. All these different approaches are combined to estimate the photon production rate.

UR - http://www.scopus.com/inward/record.url?scp=85153173212&partnerID=8YFLogxK

M3 - Conference article

AN - SCOPUS:85153173212

SN - 1824-8039

VL - 430

JO - Proceedings of Science

JF - Proceedings of Science

M1 - 169

T2 - 39th International Symposium on Lattice Field Theory, LATTICE 2022

Y2 - 8 August 2022 through 13 August 2022

ER -