Thermoluminescence of fluorapatite mineral

Autor(es)

Silva, G. P. S. ^[1] ; Nunes, M. C. S. ^[1] ; Ulsen, C. ^[2] ; Kunzel, R. ^[3] ; Yoshimura, E. M. ^[4] ; Trindade, N. M. ^{[4, 1]}

Afiliação do(s) autor(es)

^[1] Fed Inst Educ Sci & Technol Sao Paulo, Dept Phys, Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Escola Politecn, Technol Characterizat Lab, Sao Paulo, SP - Brazil

^[3] Univ Fed Sao Paulo, Dept Phys, Diadema, SP - Brazil

^[4] Univ Sao Paulo, Inst Phys, Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Luminescence; v. 231, MAR 2021.
• Citações Web of Science: 0

Resumo

Fluorapatite {[}Ca-10(PO4)(6)F-2] is a mineral of the apatite group of the highest occurrence in the world among phosphates. The material is known for its diverse luminescent properties, as fluorescent lamps and lasers. The thermoluminescence (TL) signal of apatite from various origins has been investigated in the past years, mainly of the Mexican origin. In this work, the objective was to investigate the TL of samples of the Brazilian natural fluorapatites submitted to beta-ionizing radiation. The chemical composition of the samples was obtained by the technique of X-ray fluorescence and the electronic transitions were verified by optical absorption in the visible region. The mineral presented a wide optical absorption band between 500 nm and 750 nm, typical of fluorapatite, and SEM/EDS showed a high percentage of purity. The registered Raman spectrum exhibits the characteristics modes from the PO43- tetrahedra, observed in fluorapatite, and a band at 1103 cm(-1) characteristic of the (CaO3)(2-) carbonate group. The TL measurements were carried out using a commercial Riso TL/OSL reader, model DA-20, equipped with a built in Sr-90/Y-90 beta source, with different radiation doses (1-5 Gy). The TL glow curve showed three peaks located at about 350 K, 470 K and 570 K (heating rate of 1 K/s). The activation energy and the frequency factor associated with each peak were determined by different methods. In addition, the TL response (area under the peaks) has shown linear behavior in relation to the doses. (AU)

• Processo FAPESP: 19/05915-3 - Caracterização de minerais para dosimetria luminescente das radiações ionizantes
• Beneficiário: Neilo Marcos Trindade
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/16894-4 - Investigação da luminescência opticamente estimulada de pastilhas de alexandrita para aplicações na área de dosimetria
• Beneficiário: Matheus Cavalcanti dos Santos Nunes
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 19/15599-1 - Investigação da termoluminescência de fluorapatita com foco na área de dosimetria
• Beneficiário: Guilherme Paulino dos Santos Silva
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica