Speaker
Description
Thermal photons from the QGP provide important information about the interaction among the plasma constituents. The thermal photon production rate from a thermally equilibrated plasma is proportional to the transverse spectral function $\rho_{T}(k_0=|\vec k|,\vec k)$. One can calculate the photon production rate also from the difference between $\rho_{T}$ and $\rho_{L}$(longitudinal) correlator as $\rho_{L}$ vanishes on the photon point. The UV part of $\rho_{T}-\rho_{L}$ is not dominant and therefore the corresponding Euclidean correlator gets most of the contribution from the IR part of $\rho_{T}-\rho_{L}$. We calculate the continuum extrapolated T-L correlator non-perturbatively on the lattice at 1.1$T_c$ and 1.5$T_c$ for a gluonic medium. We will present the extraction of spectral function from this Euclidean correlator using a hydrodynamic inspired model in combination with the Backus-Gilbert method, which allows us to estimate the photon production rate at these temperatures.
