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The aim of this study was to evaluate the reliability of Fricke gel-layer dosimeters for the measurement of in-phantom dose distributions produced by a ((192))Ir brachytherapy source. The doses obtained were compared to measurements performed with thermoluminescent dosimeters and treatment planning calculations. Fricke gel-layer dosimeters have proven to be a promising tool to measure three-dimensional dose distributions in high dose-rate brachytherapy., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Gel dosimetry has been studied mainly for medical applications. The radiation induced ferric ions concentration can be measured by different techniques to be related with the absorbed dose. Aiming to assess gamma/thermal neutrons dose from research reactors, Fricke gel and alanine gel solutions produced at IPEN using 300 bloom gelatin were mixed with Na(2)B(4)O(7) salt, and the mixtures were irradiated at the beam hole #3 of the IEA-R1 research reactor, (BH#3) adapted to BNCT studies, and the dose-response was evaluated using spectrophotometry technique., (Copyright 2010 Elsevier Ltd. All rights reserved.)

A potential dosimeter based on aqueous frozen solutions and solid-state salt are presented for the evaluation of the energy transferred during the interaction of high-energy radiation with matter at low temperature. The foundation of these dosimeters, both the solid state and the frozen solutions, is based on the measurement of the change of the iron oxidation state. The systems were irradiated with gamma radiation at different doses (up to 10 MGy), and at different temperatures (from 77 to 298 K). The irradiated samples were analysed by UV-spectroscopy and Mössbauer spectroscopy. A theoretical model was developed for the chemical reactions system. This model reproduces the experimental effects produced by the irradiation in aqueous solutions of ferrous salt. The results showed that the response of the dosimeters depends on the irradiation temperature. At low-radiation doses, the response was linear. In particular, this work can be applied to low-temperature dosimetry can be specially applied to simulation experiments of extraterrestrial bodies, as well as in general to space research., (c2004 Published by Elsevier Ltd.)