  We calculate thermal photon and electron pair distribution from hot QCD
matter produced in high energy heavy-ion collisions, based on a hydrodynamical
model which is so tuned as to reproduce the recent experimental data at CERN
SPS, and compare these electromagnetic spectra with experimental data given by
CERN WA80 and CERES. We investigate mainly the effects of the off-shell
properties of the source particles on the electromagnetic spectra.
