title: Study of suitability of Fricke-gel-layer dosimeters for in-air measurements to characterise epithermal/thermal neutron beams for NCT.
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 3mm, 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.
authors.affiliation: Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy. Electronic address: grazia.gambarini@mi.infn.it.
authors.forename: G
authors.initials: G
authors.lastname: Gambarini
authors.affiliation: Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Artuso
authors.affiliation: Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Giove
authors.affiliation: Department of Physics, Università degli Studi di Milano, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Felisi
authors.affiliation: Department of Physics, Università degli Studi di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Volpe
authors.affiliation: Energy Department, Politecnico di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Barcaglioni
authors.affiliation: Energy Department, Politecnico di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Agosteo
authors.affiliation: Energy Department, Politecnico di Milano, Milan, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Garlati
authors.affiliation: Energy Department, Politecnico di Milano, Milan, Italy; INFN, Istituto Nazionale di Fisica Nucleare, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Pola
authors.affiliation: Department of Neutron Physics, Research Centre Řež, Czech Republic.
authors.forename: V
authors.initials: V
authors.lastname: Klupak
authors.affiliation: Department of Neutron Physics, Research Centre Řež, Czech Republic.
authors.forename: L
authors.initials: L
authors.lastname: Viererbl
authors.affiliation: Department of Neutron Physics, Research Centre Řež, Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Vins
authors.affiliation: Department of Neutron Physics, Research Centre Řež, Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Marek
mesh_terms: D008962:Models, Theoretical; D009010:Monte Carlo Method; D017247:Neutron Capture Therapy / Q000295:instrumentation*; D011879:Radiotherapy Dosage
keywords: Epithermal neutron dosimetry; Fricke-gel dosimeter; Monte-Carlo simulation; Reactor dosimetry; TLD