Pion and photon bremsstrahlung in a heavy ion reaction model with friction

Based on a classical dynamical model of nuclear motion with a velocity dependent friction force we calculate pionic and electromagnetic bremsstrahlung emitted in heavy ion collisions with bombarding energies between 20 and 84 MeV/n. For arbitrary projectile-target combinations and with a fixed value of the only parameter of the model, the friction coefficientκ, our calculations reproduce the observed beam energy and target mass dependence for pions. The gamma yields, calculated with the same value ofκ, reproduce the measured dependence of the cross-section on energy and target mass, but underestimate the published data by a factor two. This is a good agreement in view of the discrepancies between different experimental groups.