Plastic scintillator doped with neutron-sensitive plutonium and method for measuring thermal neutrons

Abstract

The invention belongs to the radiation measurement field and relates to a neutron-sensitive substance plutonium-doped plastic scintillator and a thermal neutron measurement method thereof. According to the neutron-sensitive substance plutonium-doped plastic scintillator and the thermal neutron measurement method thereof of the invention, a plastic scintillator is doped with a plutonium-containing raw material; the plutonium-doped plastic scintillator is connected with a photomultiplier tube, and the plutonium-doped plastic scintillator and the photomultiplier tube are sealed in an opaque shell, so that a probe can be formed; the probe is arranged in a measurement environment; incoming neutrons and the plutonium-containing raw material in the plastic scintillator are subjected to a nuclear reaction, so that the material is in an excited state; after the material is de-excited, photons are released; the number of the photons is proportional to the number of the incoming neutrons; the quantity of the electric pulse signals of the photomultiplier tube in unit time is recorded, so that the fluence of the neutrons can be obtained, and therefore, the measurement of the fluence of the neutrons can be realized; and the fluence of the neutrons is multiplied by a fluence-dose conversion coefficient, so that the equivalence of the dose of the neutrons can be obtained. The neutron-sensitive substance plutonium-doped plastic scintillator of the invention has the advantages of low cost, wide application range and high detection efficiency.

Description

technical field [0001] The invention belongs to the field of radiation measurement, in particular to a plastic scintillator doped with plutonium, a neutron-sensitive material, and a method for measuring thermal neutrons. Background technique [0002] Plastic scintillators are generally made of polystyrene as a matrix, mixed with other organic additives as scintillating substances, and made of wave shifting agents. It has high detection efficiency, high light output, narrow signal pulse width, good processability, Due to the advantages of strong environmental adaptability, stable mechanical properties, and low cost, it is widely used in radiation measurement work. However, since the main components of plastic scintillators are C, H, and O, their interaction with neutrons is relatively low, and generally cannot It is directly used in the field of neutron monitoring. Therefore, when detecting neutrons, other materials need to be doped or embedded to increase the output of optic...

AI Technical Summary

Problems solved by technology

[0003] Since the ZnS:Ag film is opaque, the method of embedding the ZnS:Ag film in the plastic scintillator will lose a lot of photons, resulting in a decrease in detection efficiency and sensitivity

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