The role of nuclear incompressibility in the production of hard photons in heavy-ion collisions

We summarize the properties of hard photons emitted in heavy-ion collisions. Dynamical phase-space calculations are used to describe the initial phase of the collision. Guided by the predictions, the photon spectra and the two-photon interference pattern are interpreted as a result of the collision dynamics and the photon spectra are viewed as an image of the phase space occupancy of participating nucleons. The data demonstrate the existence of two spatially and temporally distinct photon sources. It is shown how their relative intensity provides us with a measure of the incompressibility modulus of infinite nuclear matter.