Nuclear Technology / Volume 168 / Number 1 / October 2009 / Pages 113-117
Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection
To improve radiation safety in high-energy accelerator facilities, the authors have been developing the new radiation dose monitor device DARWIN: Dose monitoring system Applicable to various Radiations with WIde energy raNges. DARWIN is composed of (a) a phoswitch-type scintillation detector, which consists of liquid organic scintillator BC501A coupled with ZnS(Ag) scintillation sheets doped with 6Li, and (b) a data acquisition (DAQ) system for digital analysis of the waveform of the scintillator signals. The DAQ system was recently updated in order to apply DARWIN in monitoring dose rates in radiation fields having time structure, introducing an originally developed module based on a field-programmable gate array. To examine the performance of DARWIN placed in radiation fields composed of varieties of particles over wide energy ranges, the authors mounted DARWIN on a jet aircraft and measured neutron, photon, muon, electron, and positron dose rates at high altitudes. The measured dose rates excellently agreed with the corresponding data calculated by EXPACS over a wide altitude range. This agreement indicates the applicability of DARWIN to dose monitoring in complex radiation fields such as those in high-energy accelerator facilities and aircrafts.