Instrumentation and testing of a low-cost TL/RL system.

Abstract

The plan provides for the specific collaboration of the visiting professor with the project "Characterization of Minerals for Luminescent Dosimetry of Ionizing Radiation", process 2019/05915-3. The project is being developed in partnership with the IFUSP Radiation Dosimetry and Medical Physics Group, which is part of the National Institute of Science and Technology (INCT) of Metrology of Radiation in Medicine. In this project, a homemade radioluminescence system combined with spectral thermoluminescence (TL/RL) is being developed. Thermoluminescence (TL) and radioluminescence (RL) have been widely used to evaluate materials for application in dosimetry. TL is the light emitted by some crystals when heated, being a thermally stimulated emission of energy that was previously stored in the material during irradiation. Likewise, RL corresponds to the luminescence emitted by a material exposed to ionizing radiation. As this is a luminescence that occurs during stimulation with ionizing radiation, it is possible to identify which wavelengths are emitted by the sample, and thus, analyze which impurities (chemical elements) and or defects are responsible for its luminescence, a fact that always is questioned by reviewers of articles submitted in this area. Furthermore, among the energy levels of a crystal, some trapping levels are not influenced by RL, while all trapping levels are more significantly influenced by TL. Additionally, the combination of RL and TL properties can provide more information to establish models for the capture and recombination centers involved in luminescent processes, since the processes compete with each other during the trapping of charge carriers. Therefore, through the analysis of these luminescence curves obtained from RL and TL, it is possible to obtain more extensive information about the levels of entrapment than in the case of individual treatment. Furthermore, knowledge of the emission spectrum is useful to optimize light collection in dosimetric detectors. In this study, an integrated TL/RL measurement device will be developed to more accurately analyze the luminescence mechanism of materials. All inputs for the execution of this project have already been acquired and, therefore, the mechanical and electronic assembly phase can already be started, an area of expertise for the visiting researcher. The visiting researcher will also assist in the first tests with standard samples and subsequently in the study materials. In addition, the establishment of relationships in a network format will be promoted with other Research Groups that investigate the same theme, for example, University of São Paulo, in addition to the promotion of courses, conferences and seminars for Research Groups and for the Postgraduate Program - Mechanical Engineering from IFSP. Finally, the purpose of the visiting researcher is to advise the team regarding the research methodology in instrumentation and testing of the TL/RL measurement system, in addition to promoting high-level theoretical studies on topics such as "Physical Instrumentation" and "Physics of Materials" applied to dosimetry. (AU)