Speaker
Description
ISOLDE is a CERN facility dedicated to the production of radioactive ion beams for applications in atomic physics, nuclear astrophysics, fundamental interactions, and life sciences. The 1.4 GeV proton beam, coming from the Proton Synchrotron Booster (beam power of 2.8 kW) impinges on a thick target kept at high temperature during irradiation. The generated radionuclides diffuse out of the target and are subsequently ionized, extracted and finally selected using a mass separator. About 60-70% of the primary proton beam does not interact with the target and is intercepted by a beam dump (one for each of the two target stations). The ISOLDE beam dumps are currently operating at their limit in terms of temperature and mechanical stresses and, therefore, their replacement is currently being studied.
To this extent, a radiological characterization, in terms of radionuclide inventory and residual dose rate, of the radioactive materials that will be removed during the dismantling phase, was performed. The presentation will focus on the methodology employed to characterize the various radioactive items (concrete shielding blocks, steel beam dumps, soil shielding); Monte Carlo simulations were performed with the FLUKA code distributed by CERN and, where possible, were benchmarked and complemented with information from experimental measurements. The study provides extensive information that are being used to plan the dismantling worksite, the potential elimination pathways and the required radiation protection measures necessary for safe removal, handling, transport and storage of the radioactive materials.
