Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Efficiency calculation of the nMCP with 10B doping based on mathematical models

  • Received : 2020.05.12
  • Accepted : 2021.01.25
  • Published : 2021.07.25
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Abstract

The nMCP (Neutron sensitive microchannel plate) combined with advanced readout electronics is widely used in energy selective neutron imaging because of its good spatial and timing resolution. Neutron detection efficiency is a crucial parameter for the nMCP. In this paper, a mathematical model based on the oblique cylindrical channel and elliptical pore was established to calculate the neutron absorption probability, the escape probability of charged particles and overall detection efficiency of nMCP and analyze the effects of neutron incident position, pore diameter, wall thickness and bias angle. It was shown that when the doping concentration of the nMCP was 10 mol%, the thickness of nMCP was 0.6 mm, the detection efficiency could reach maximum value, about 24% for thermal neutrons if the pore diameter was 6 ㎛, the wall thickness was 2 ㎛ and the bias angle was 3 or 6°. The calculated results are of great significance for evaluating the detection efficiency of the nMCP. In a subsequent companion paper, the mathematical model would be extended to the case of the spatial resolution and detection efficiency optimization of the coating nMCP.

Keywords

Acknowledgement

This work was supported by the National Key R&D Program of China [Grant No. 2017YFA0403702], the National Natural Science Foundation of China [Grant No. 11635012, 11775243, U1832119], Youth Innovation Promotion Association CAS, Guangdong Basic and Applied Basic Research Foundation (Grant No. 2019A1515110217).

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