Radioactivation Measurement of a Protective Collimator and Comparisons with Simulation After METU-Defocusing Beamline Pretest Irradiation

Electronic components must be tested to allow for safe and reliable missions in radiation environments. The METU Defocusing Beamline (METU-DBL) was installed in the R&D room at the Particle Accelerator Facility (PAF) of Turkey Energy, Nuclear and Mining Research Institute (TENMRI) to perform proton irradiation tests for these electronic components in accordance with the ESA (European Space Agency) ESCC (European Space Components Coordination) No:25100 standard. METU-DBL uses beam elements such as quadrupole magnets and collimators to enlarge the beam and decrease the flux respectively for the specifications of the standard. A pretest setup was constructed and this system was operated for a total of 17 hours for three months before the METU-DBL final design was assembled. The first protective collimator is made of stainless steel 316L and was used during the period of pretests. As a result of these irradiations, the emerged radioisotopes in the collimator were observed and measured insitu with a NaI detector. These measurements were compared with the FLUKA simulations 120 days after the last irradiation. Among fourteen radioisotopes, only six of them with activity above 1.0×101 Bq/cm3 were matched.