Radiation Degradation of Silicon Crystal Used as Filter for Neutron Radiography
Ladislav Viererbl, Jaroslav Šoltés, Miroslav Vinš, Hana Assmann Vratislavská, Alexander Voljanskijdownload PDF
Abstract. Single crystals of some materials like silicon, sapphire or bismuth are often used as radiation filters for neutron radiography beams. These single crystals are relatively transparent for thermal and cold neutrons and can suppress fast neutrons and gamma radiation. When a single crystal is irradiated the crystal lattice is partially damaged and filter characteristics of the crystal can be deteriorated. This aspect of radiation degradation was studied for silicon single crystals. Experiments for silicon radiation degradation measurements were carried out in the LVR-15 research reactor. A silicon crystal sample (length of 10 cm) was irradiated in the reactor core. Thermal neutron attenuation was measured on the thermal neutron beam used also for neutron radiography facility. The attenuation measurement was made by activation detectors before and after crystal irradiation in the reactor core. A silicon single crystal (length of 100 cm) is used as a neutron filter in the channel used for neutron radiography in the LVR-15 reactor. The results indicate that the radiation degradation of the filter is acceptable low for a few years of facility operation.
Radiation Degradation, Neutron Filter, Silicon Crystal, Neutron Radiography
Published online 1/5/2020, 5 pages
Copyright © 2020 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Ladislav Viererbl, Jaroslav Šoltés, Miroslav Vinš, Hana Assmann Vratislavská, Alexander Voljanskij, Radiation Degradation of Silicon Crystal Used as Filter for Neutron Radiography, Materials Research Proceedings, Vol. 15, pp 53-57, 2020
The article was published as article 9 of the book Neutron Radiography
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