Thermal Dilepton Rates and Meson Spectral Functions from Lattice QCD
Abstract
Description
Pseudo-scalar and vector meson correlation functions were calculated at temperatures below and above the deconfinement transition using ${\cal O}(a)$ improved Wilson fermions in quenched lattice QCD. The spectral functions were reconstructed from the correlator given only at discrete points in Euclidean time by means of the Maximum Entropy Method without a priori assumptions on the spectral shape. The deviation of the spectral functions from the one of a freely propagating quark anti-quark pair is examined above the critical temperature. At 1.5 and 3 $T_c$ the vector spectral function yields an enhancement of the dilepton rate over the Born rate in the energy interval $4 < ω/T < 8$ and a sharp drop at energies below 2-3 T.
Contribution to the proceedings of the International Workshop XXX on Gross Properties of Nuclei and Nuclear Excitations - Ultrarelativistic Heavy-Ion Collisions, January 13-19, 2002, Hirschegg, Austria, 6 pages
Contribution to the proceedings of the International Workshop XXX on Gross Properties of Nuclei and Nuclear Excitations - Ultrarelativistic Heavy-Ion Collisions, January 13-19, 2002, Hirschegg, Austria, 6 pages