Medium modification of sigma meson production in heavy ion collisions

The sigma meson is a broad resonance and even the pole mass is not precisely determined. Therefore the meson is very difficult to identify from the experimental side. Sigma meson production has not yet been measured in heavy ion reactions. Recently, sigma meson production has been measured in photon and pion induced reactions on nuclei. The existing data provide first indications for a mass shift of the sigma in heavy nuclei. The aim of the present work is to make a prediction for such reactions and to investigate the possibility for the observation of such mass shifts. (author)