Gamma ray collimator for reference gamma radiation field

Abstract

The invention relates to the technical field of nuclear radiation measurement calibration, and provides a gamma ray collimator for a reference gamma radiation field. The gamma ray collimator comprises a collimating diaphragm, a light path of the collimating diaphragm is in the shape of a truncated cone, an incident window of the collimating diaphragm is flared, a launch window of the collimating diaphragm is extended based on the edge of the light path, a plurality of annular grooves are formed in the inner surface of the collimating diaphragm, the sections of the annular grooves are triangular, vertexes of all triangles in the same section are positioned on the same horizontal plane, bottom edges of all the triangles are positioned on the same edge of the light path, the triangular sections of the annular grooves are varied with energy of radioactive source gamma ray energy, and different energy dispersion gamma photons are scattered backwards. Scattered gamma photon reduction capacity of the reference gamma radiation field collimator can be improved, and uniformity and accuracy of the radiation field are improved.

Description

technical field

[0001] The invention relates to the technical field of nuclear radiation metrology calibration, in particular to a gamma ray collimator for referring to a gamma radiation field. Background technique

[0002] The establishment of a reference radiation field is the key to nuclear radiation metrology technology, and its accuracy and uncertainty are important indicators to measure the quality of a reference radiation field, which directly affects the scope of use of reference radiation. According to the relevant technical requirements of GB / T12162, the scattering effect of the reference gamma radiation field should not exceed 5%, and the deviation of the radiation field dose rate at different distances from the inverse square rate should not exceed 5%. There are many factors that produce scattered photons, mainly including ray collimator, spatial layout of the radiation room, and auxiliary facilities of the device. For the spatial layout of the radiation room, t...

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