Fast and slow neutron combined detector

Abstract

The invention relates to a fast and slow neutron combined detector, which is characterized in that the main structure is a cylindrical plastic scintillator, the plastic scintillator is internally provided with blind holes, and the blind holes are uniformly arranged in a layered manner; lithium glass scintillation columns are placed in the blind holes, a contact surface of each lithium glass scintillation column and the plastic scintillator is coupled by using an optical coupling agent; a light window surface of the plastic scintillator adopts polishing treatment, and the other outer surfaces are subjected to grinding treatment; the plastic scintillation is coated with a reflecting layer except for the light window surface, and the reflecting surface is externally covered by a shell; and the light window surface of the plastic scintillation is packaged with a light window by adopting an optical adhesive, the light window serves as a light leading-out surface, and the scintillation lightis led out by the light window. The plastic scintillator is used for measuring incident fast neutrons, the lithium glass adopts a multilayer structure, the number of lithium glass scintillation columns in each layer increases layer by layer from the inside out, and number of layers is preferably to be three. The outer layer and the inner layer are used for detecting incident slow neutrons, the inner layer and the central lithium glass can measure the slow neutrons slowed down by the plastic, and the sensitivity of the incident fast neutrons and the sensitivity of the slow neutrons are improved at the same time.

Description

technical field [0001] The invention relates to the field of neutron detection in nuclear radiation measurement technology, in particular to a fast and slow neutron composite detector. Background technique [0002] Neutron measurement is an important part of nuclear radiation monitoring technology. According to different applications, a variety of measuring instruments have been developed, such as neutron flux rate meter, neutron energy spectrometer, neutron dose equivalent meter, etc. The most commonly used neutron detectors are: 3 He proportional counter, BF 3 proportional counter, 6 Li glass scintillator, plastic scintillator, liquid scintillator, etc. The detectors commonly used at this stage are only sensitive to neutrons in a specific energy range, while the sensitivity to other energy ranges is extremely low. For example, the first three items listed are slow neutron detectors, and the last two items are fast neutron detectors. For neutron detection, it is a neces...

AI Technical Summary

Problems solved by technology

But with mixing 6 As the Li concentration increases, the transparency of the plastic scintillator decreases significantly, and the neutron sensitivity decreases significantly. This process needs to be improved.

In addition 6 The production process of Li plastic scintillators is complicated, and it needs to be introduced during the polymerization of plastics. 6 Li nuclide, 6 Li is easily distributed unevenly, resulting in different detectors

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