High-current pulse wide-energy-spectrum neutron dose rate monitoring device

Abstract

The invention discloses a high-current pulse wide-energy-spectrum neutron dose rate monitoring device. The monitoring device comprises a counting electronics system, a neutron moderator, a multi-anode photomultiplier and four plastic scintillator detectors with the same size; the counting electronics system is connected with the multi-anode photomultiplier through a connecting wire; the plastic scintillator detectors are cuboid, one surface of each plastic scintillator detector is connected with the multi-anode photomultiplier, and the other surfaces of every two plastic scintillator detectors are respectively wrapped by a silver film and a tin film; the four plastic scintillator detectors are fixed at the central position of the neutron dose rate monitoring device by adopting epoxy plastic; the neutron moderator is arranged outside the epoxy plastic, is spherical and sequentially comprises an outer polyethylene layer, a heavy metal spallation layer, a neutron absorption layer and an inner polyethylene layer from outside to inside. The dependency of the neutron dose rate monitoring device on a neutron incident angle is within + / -1%; the megahertz counting capability is achieved, and the saturation phenomenon is not prone to occurring in a strong neutron or photon radiation field.

Description

technical field [0001] The invention relates to a dosimeter, in particular to a neutron dose rate monitoring device with a strong current pulse width energy spectrum. Background technique [0002] A common neutron dosimeter consists of a thermal neutron detector and a neutron moderator. Thermal neutron detectors are mainly helium 3 tubes or boron trifluoride tubes. Helium 3 and boron 10 have a large reaction cross section with thermal neutrons; neutron moderators are composed of hydrogen-rich materials. This kind of neutron dosimeter has the advantages of high sensitivity to neutrons, resistance to gamma radiation, anti-electromagnetic interference, etc., and has been widely used in neutron dose monitoring of accelerators and reactors at home and abroad. However, in the pulsed neutron field of this neutron dosimeter, due to the influence of dead time, the measured neutron dose is smaller than the real neutron dose. [0003] Patent US8642971B2 discloses a neutron dosimeter,...

AI Technical Summary

Problems solved by technology

The disadvantages of this neutron dosimeter are: a. Since only polyethylene is used to moderate neutrons, the response to high-energy neutrons is very low, and the dose rate of high-energy neutrons cannot be measured; b. The sensitive volume of the detector is 4 8.5×10.5×0.48mm 3 The silicon semiconductor makes the dosimeter highly dependent on the incident angle of neutrons; c. The count rate of the silicon semiconductor detector is on the order of hundreds of kHz, and it is prone to saturation in the strong neutron or photon radiation field

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