A kind of α, β ray detector

Abstract

The invention relates to a ray detector, in particular to an alpha and beta ray detector in the form of a combination of a thin plastic scintillator and a photomultiplier tube. The invention prevents external photons from entering the interior of the detector as much as possible through structural design, improves the light collection efficiency of the inner surface of the detector, and increases the ray transmission area of ​​the detection window. The light protection of the detection window is mainly achieved by the elastic contact between the black silicone ring and the plastic scintillator, light protection film, housing side wall, and protective cover. The inner surface of the detector housing is coated with aluminum film to make the scintillation light reflection coefficient greater than 0.9, and the four walls of the detector housing are designed as slopes to reduce the number of reflections of the scintillation light in the detector housing, so that photons can be gathered quickly. There are two forms of detection window protective cover grid, one is honeycomb hexagonal grid, the transmittance of vertical incident rays is greater than 90%. The other is the combination of hexagonal grid and stainless steel gauze, the transmittance of vertical incident rays is greater than 75%. Simple structure, strong maintainability and high detection efficiency.

Description

technical field [0001] The invention relates to an α and β ray detector, in particular to an α and β ray detector in the form of a combination of a thin plastic scintillator and a photomultiplier tube. Background technique [0002] The α and β ray detectors are sensors for personnel's whole body α and β pollution monitors, hand and foot α and β pollution monitors, etc., which can quickly detect the α and β rays contaminated on the surface of the human body to determine whether the personnel are radioactively polluted . It is mainly used in personal pollution monitoring in nuclear power plants, nuclear processing plants, nuclear warehouses and other radioactive workplaces. [0003] The principle of α and β-ray detectors in the form of a combination of thin plastic scintillators and photomultiplier tubes is: when the rays enter the thin scintillator, the atoms or molecules of the scintillator are ionized or excited, and when de-excitation, part of the ionization or excitation...

AI Technical Summary

Problems solved by technology

[0006] In the past detectors, the thin plastic scintillator, light-shielding film, detector housing, and protective cover are in hard contact. In order to achieve the ideal light-shielding effect, black liquid silicone is used to protect the contact edges of these four during assembly. It is difficult to open the detector again, which is not conducive to on-site maintenance. At the same time, the film and shell are also damaged, which is difficult to recycle and reuse, resulting in waste

[0007] In the past, the protective cover grid of the detector used a thin metal plate with several square holes, and its own ray transmittance could not be made very high (<60%) due to the limitation of the punching process, so that the effective detection area of ​​the detector was greatly increased. reduce

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