SOFT PHOTONS FROM OFF-SHELL PARTICLES IN A HOT PLASMA

Considering the propagation of off-shell particles in the framework of thermal held theory, we present the general formalism for the calcula tion of the production rate of soft photons and dileptons from a hot p lasma. This approach is first illustrated with an electrodynamic plasm a. The photon production rate from strongly interacting quarks in the quark-gluon plasma, which might be formed in ultrarelativistic heavy i on collisions, is also calculated. We utilize an effective field theor y incorporating dynamical chiral symmetry breaking and obtain results in the previously inaccessible regime of photon energies of the order of the plasma temperature.