Study of suitability of Fricke-gel-layer dosimeters for in-air measurements to characterise epithermal/thermal neutron beams for NCT. (December 2015)

• Record Type: Journal Article
• Authors: Gambarini, G.; Artuso, E.; Giove, D.; Felisi, M.; Volpe, L.; Barcaglioni, L.; Agosteo, S.; Garlati, L.; Pola, A.; Klupak, V.; Viererbl, L.; Vins, M.; Marek, M.
• Is Part Of: Applied radiation and isotopes. Volume 106(2015:Dec.)
• Page Start: 145
• Page End: 150
• Publication Date: 2015-12
• Subjects: Reactor dosimetry -- Epithermal neutron dosimetry -- Fricke-gel dosimeter -- Monte-Carlo simulation -- TLD; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2015.07.036
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: The reliability of Fricke gel dosimeters in form of layers for measurements aimed at the characterization of epithermal neutron beams has been studied. By means of dosimeters of different isotopic composition (standard, containing 10 B or prepared with heavy water) placed against the collimator exit, the spatial distribution of gamma and fast neutron doses and of thermal neutron fluence are attained. In order to investigate the accuracy of the results obtained with in-air measurements, suitable MC simulations have been developed and experimental measurements have been performed utilizing Fricke gel dosimeters, thermoluminescence detectors and activation foils. The studies were related to the epithermal beam designed for BNCT irradiations at the research reactor LVR-15 (Řež). The results of calculation and measurements have revealed good consistency of gamma dose and fast neutron 2D distributions obtained with gel dosimeters in form of layers. In contrast, noticeable modification of thermal neutron fluence is caused by the neutron moderation produced by the dosimeter material. Fricke gel dosimeters in thin cylinders, with diameter not greater than 3 mm, have proved to give good results for thermal neutron profiling. For greater accuracy of all results, a better knowledge of the dependence of gel dosimeter sensitivity on radiation LET is needed. Highlights: Fricke gel dosimeters in form of layers were deeply inspected. Suitability of gel dosimeters for characterization of epithermal beams was determined. Proper dosimeter shape and dimension were identified. Good consistency between measurements and MC simulations was found.