| 摘要 |
A detector signal-processing circuit 8 comprises the following: a current/voltage conversion part 21 that converts the current value of a neutron detector 3 to a voltage value; a variable gain amplification part 22 that performs amplification by a first-step variable gain using a D/A converter 53; a current level response-use resistance circuit 41 that selects the measurement range in accordance with the voltage value; temperature measurement units 82, 83, and 84 for measuring the temperature of the resistance circuit 41 for current level response; a temperature compensation part 81 for commanding gain compensation by the D/A converter 53 on the basis of the measured temperature; and a selective adjustment control part 26 for selective control of the measurement range and adjustment of the variable gain of the variable gain amplification part 22. Due to this configuration, neutron flux can be measured with high precision while maintaining a constant output precision, before and after switching of the measurement range. |
