ASSESSMENT OF PERSONNEL ABSORBED DOSE AT PRODUCTION OF MEDICAL RADIOISOTOPES BY A CYCLOTRON

The medical radioisotope 201Tl is produced by a cyclotron through the 203Tl(p, 3n)201Pb reaction in the nuclear medicine research group of Agricultural, Medical and Industrial Research Schools in Iran. The produced 201Pb decays to 201Tl by electron capture. One of the most important problems that may occur is malfunction of a part of target or beam line, so that it needs the bombardment to be stopped and the problem fixed. In this work, induced radioactivity of the target, aluminium case of target, beam line and concrete walls of the thallium target room were calculated by Monte Carlo method. Then by using the results of the Monte Carlo simulation, the whole body absorbed dose to cyclotron personnel during repair and after stopping the bombardment, were assessed at different places of target room.