Patent ID: 9733368
Date: 2017-08-15
CPC Classifications: G01T,G21C

Claim:
1. A neutron measurement apparatus to measure neutron intensity in a region where a nuclear reactor power is lower than a predetermined Power Range, the apparatus comprising: a neutron detector to generate an output signal corresponding to an incoming neutron; a preamplifier to amplify an output signal of the neutron detector to output the amplified output signal of the neutron detector as a neutron detection signal; a pulse counter to measure neutron intensity by using a pulse counting method by which the neutron detection signal is used to count a number of individual pulses; a Campbell meter to measure the neutron intensity by using a Campbell method by which a time average of squares of an AC component of the neutron detection signals is calculated; a correction constant calculator to calculate a correction constant for correcting an output of the Campbell meter by using an output of the pulse counter and an output of the Campbell meter; and a correction value calculator that outputs, based on the output of the Campbell meter, a corrected value by using the correction constant, wherein the correction constants are a gain “a” and an offset “b” that are calculated by regression calculation expressed by the following formula (1), in a region where linearity of input and output can be obtained in the pulse counter, and the corrected value “Y′” is calculated by the following formula (2): where X represents the output of the pulse counter and Y represents the output of the Campbell meter at a same moment.