Threshold radiation dose detector - for neutron and gamma radiation with dose rate/interlock

摘要

Each of esp. three detector probe heads in a "two out of three" alarm signal system is a double scintillometer with a front scintillator plate of esp. gamma-sensitive material and a rear plate of slow neutron sensitive scintillator material, the whole being encased in a jacket of moderator material esp. polyethylene which gives the best compromise match between the sensitivities of the two plates for different relative thicknesses. An R-C network at the photoelectric device output to the threshold detector stage has a switch to disconnect the capacitor, so that the alarm system is operated not only after the threshold dose for safety is exceeded, but also when the dose rate has passed a predetermined limit.