High level of electromagnetic radiation is produced in the interaction of relativistic ions with matter. A model to simulate it within GEANT4 has been developed in order to evaluate these sources of background and their influence on the experimental spectra. New classes have been added to the standard GEANT4 program libraries, describing the radiative electron capture, primary bremsstrahlung and secondary bremsstrahlung processes. Simulations of experiments within the RISING stopped beam campaign and comparison with the experimental results are presented.

PACS numbers: 25.75.--q, 25.70.--z, 25.70.Pq