MEASUREMENT OF ACTIVATION INDUCED BY AN ARGON BEAM IN A COPPER TARGET AT THE SIS18

Several laboratories in the world have started or plan to build new powerful ion accelerators. These facilities promise to provide very valuable tools for experiments in fundamental nuclear physics, physics of high energy density in matter and for medical applications as well. One of the most important problems that have to be solved during the design stage is the radiation protection of the accelerator. Due to the complexity it is hardly possible to obtain reliable radionuclide production data for accelerator structure materials from radiation transport codes. Thus, the experimental data which can be measured at the presently existing facilities (SIS-18, Ganil) are necessary for the evaluation of the induced levels of radioactivity around intense heavy ion accelerators. Results of the measurement of activation induced by Argon beam with energies of E = 300, 500, 800 MeV/u in the copper target are presented in this paper. MOTIVATION In recent years, requirements from new technological and research applications for particle accelerators have emerged, giving rise to new radiation shielding aspects and problems. For the new high-power accelerators currently being designed, activation of the accelerator structure has become an important issue. The main emphasis of new heavy ion accelerator projects (SIS-100, TWAC or future HIDIF) focuses on the technical developments needed to increase the achievable beam intensities by up to two orders of magnitude. The activation, however, produced by accelerators of such high power, has not yet been quantified. Hence, novel safety aspects evolving from the increased radioactive inventory of such facilities will obviously play the major role in the design and approval procedure. The experimental investigation of potential radiation risks during normal heavy ion accelerator operation is proposed in a new GSI-INTAS project. Three main topics that have to be investigated in this direction are as follows: 1. Characterization of radiation from selected components of the beam line, especially from the extraction section: production rates of radioactive nuclides