Radiophotoluminescent dosimetric system for personal and overall radiation control

An experimental RPL-SC dosimetric system for measurement of absorbed doses in persons exposed to mixed gamma- and neutron field over 1 mGy has been created. The measuring principle is based on the radiophotoluminescence (RPL) and on the impact of fast neutrons on Si semiconductor diodes. RPL-SC experimental model is composed of a computerized measuring system and a personal dosimetric cassette accommodating RPL and SC detectors. In the manual mode of the system each step of the manipulator and the corresponding detector measurements are set up by the operator who changes the range in cases of overload and registers the results. When automatic mode is used, the processes of backing up the supplying and controlling of electrical circuits, the manipulator controlling, measuring, registering and data processing are entirely controlled by a specially developed programme. Main characteristics: 1) Absorbed dose range: gamma-rays - 10-3 - 102 Gy (10-1- 104 rad); thermal neutrons - 10-3 - 102 Gy (10-1- 104 rad); fast neutrons -10-3 - 30 Gy (10-1- 3.103 rad). 2) Irradiation energy: gamma-rays - 0.04 - 1.25 MeV; thermal neutrons - 0.024 eV; fast neutrons - 0.3 - 14 MeV. 3) Relative measurement error - 15%. 4) Recurrent measurement of one and the same dose. 5) Measurement time of 1 detector - 15 sec. Three measurement versions could be implemented: for RPL detectors, for SC detectors and for RPL detectors with a lower measuring range up to 2 cGy. (author)