NEUTRON DOSE EQUIVALENT METER

摘要

PURPOSE:To measure only the nueutron rays without mixing and measuring radiations such as X-rays or gamma-rays by counting the number of the discharge pulses of a boron fluoride counter in a pulse counting circuit only when the gate signal from a pulse shaping delay circuit is on and correcting the parts which are not counted as the gate signal is off by a correction circuit. CONSTITUTION:A pulse counting circuit 21 detects the release of neutron 13 with a boron fluoride counter 14 and counts the number of discharge pulses only when the gate signal S4 from a pulse shaping delay circuit 18 is on and a gate circuit 17 is driven. More specifically, said circuit counts only the part between the time t4 and t5 in a measuring curve 22. A correction circuit 23 connected to the circuit 21 determines the time distribution of the number of the neutrons in the curve 22 and calculates and corrects the number of the neutrons to be entered in the part between the time t3 and t4. The sum of the counted result of the circuit 21 and the counted result of the circuit 23 is the entire quantity of the measured neutrons and is displayed on a meter 24. Even if the pile up of the X-rays arises, only the neutron rays are exactly counted without mixing and measuring said X-rays.