Neutron detection method for reducing gamma ray interference by using GM counter tube

Abstract

The invention belongs to the radiation measurement technical field and relates to a neutron detection method for reducing gamma ray interference by using a GM counter tube.According to the neutron detection method of the invention, when a 6LiI scintillator detector applying a 6LiI scintillator is adopted to detect neutron rays in a mixed radiation field, a first voltage amplitude discrimination threshold is set in the 6LiI scintillator detector; and the signals of low-energy gamma rays detected by the 6LiI scintillator detector are filtered out. In order to eliminate the influence of high-energy gamma rays on a measurement effect, the neutron detection method of the invention includes the following steps that: (S1) a GM counter tube is set near a 6LiI scintillator; (S2) a second voltage amplitude discrimination threshold is set for the GM counter tube; (S3) first signals measured by a 6LiI scintillator detector are recorded, and second signals measured by the GM counter tube are recorded; and (S4) the second signals are multiplied by a correction coefficient, the second signals multiplied by the correction coefficient are subtracted from the first signals, so that a net neutron count rate is obtained.

Description

technical field [0001] The invention belongs to the technical field of radiation measurement, in particular to a neutron detection method using a GM counting tube to reduce gamma ray interference. Background technique [0002] As we all know, the space particle radiation environment includes not only charged particles such as protons and electrons, but also non-charged particles such as neutrons (n) and X-rays. As an important uncharged particle, neutron has been widely concerned by people, and the detection technology related to neutron has always been a research hotspot. Since neutrons are often accompanied by a large number of γ-rays, removing the interference of γ-rays on neutron signals is a research hotspot and difficulty in the field of neutron detection. The discrimination between neutrons and gamma rays is the basis of neutron detection technologies such as contraband detection, environmental radiation detection, military and deep space detection, and has extremely...

AI Technical Summary

Problems solved by technology

This method works well when the γ-ray energy is relatively low, but when the energy exceeds 1 MeV, the response caused by the high-energy γ-ray will seriously interfere with the measurement results of the neutron dose, so the commonly used pulse amplitude discrimination technology is used in When the mixed radiation field has high-energy gamma rays, a large deviation will occur (when the gamma-ray energy exceeds 1MeV, such high-energy gamma rays will also be in the 6 More energy is deposited in the LiI scintillator, thereby generating a larger pulse signal, 6 The signal amplitude detected by LiI scintillator is almost the same as the signal amplitude detected by thermal neutrons. At this time, the response caused by high-energy gamma rays will seriously interfere with the measurement results of neutron dose)

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