Characterization of neutron calibration fields at the TINT's 50 Ci americium-241/beryllium neutron irradiator. (April 2015)

• Record Type: Journal Article
• Authors: Liamsuwan, T; Channuie, J; Ratanatongchai, W
• Is Part Of: Journal of physics. Number 611(2015)
• Publication Date: 2015-04
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/611/1/012004
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: Reliable measurement of neutron radiation is important for monitoring and protection in workplace where neutrons are present. Although Thailand has been familiar with applications of neutron sources and neutron beams for many decades, there is no calibration facility dedicated to neutron measuring devices available in the country. Recently, Thailand Institute of Nuclear Technology (TINT) has set up a multi-purpose irradiation facility equipped with a 50 Ci americium-241/beryllium neutron irradiator. The facility is planned to be used for research, nuclear analytical techniques and, among other applications, calibration of neutron measuring devices. In this work, the neutron calibration fields were investigated in terms of neutron energy spectra and dose equivalent rates using Monte Carlo simulations, an in-house developed neutron spectrometer and commercial survey meters. The characterized neutron fields can generate neutron dose equivalent rates ranging from 156 μSv/h to 3.5 mSv/h with nearly 100% of dose contributed by neutrons of energies larger than 0.01 MeV. The gamma contamination was less than 4.2-7.5% depending on the irradiation configuration. It is possible to use the described neutron fields for calibration test and routine quality assurance of neutron dose rate meters and passive dosemeters commonly used in radiation protection dosimetry.