Development of a neutron detector for radiation protection monitoring

Mai Van Dien1, Nguyen Duc Tuan1, Nguyen Ngoc Quynh1, Vu Trung Tan1, Le Ngoc Thiem1, Vu Van Tien1
1 Institute for Nuclear Science and Technology, VINATOM, Vietnam

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Abstract

The paper presents the results of the development of a neutron detector for radiation protection purposes. Monte Carlo simulations, using MCNP5 code, were performed to optimize the configuration of the neutron detector. The developed detector consists of a 3He proportional counter embedded in a multi-layer moderator made of high-density polyethylene (HDPE) and Cadmium. The characteristics of the developed neutron detector including neutron fluence response and ambient dose equivalent response were calculated, analyzed and compared with those from other neutron survey meters. The simulation model and computed results were assessed through experimental measurements at the Secondary Standards Dosimetry Laboratory of the Institute for Nuclear Science and Technology (INST). A good agreement between the simulated and experimental results was observed within 9.3% for 241Am-Be source and four simulated workplace neutron fields.

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References

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