Thermoluminescence of natural BeAl2O4:Cr3+ Brazilian mineral: Preliminary studies

Autor(es)

Trindade, Neilo Marcos ^{[1, 2]} ; Kahn, Henrique ^[3] ; Yoshimura, Elisabeth Mateus ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Phys, Rua Matao 1371, BR-05508090 Sao Paulo, SP - Brazil

^[2] Fed Inst Educ Sci & Technol Sao Paulo IFSP, Rua Pedro Vicente 625, BR-01109010 Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Grad Program Mineral Engn, Av Prof Mello Moraes 2373, BR-05508900 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Luminescence; v. 195, p. 356-361, MAR 2018.
• Citações Web of Science: 3

Resumo

Alexandrite (BeAl2O4:Cr3+) is a variety of the chrysoberyl mineral widely found in Brazil. This mineral is expected to have potential as a natural dosimeter since its composition contains 19.8 wt% BeO and 80.2 wt% Al2O3, both oxides being commercially used as dosimeters. We report the investigation of thermoluminescence (TL) properties from alexandrite in natural form. Samples 1.0 mm-thick and mass of 0.045 g were cut of a stone originated in Bahia, Brazil. Sample composition was determined through x-ray fluorescence and scanning electron microscopy/energy dispersive x-ray spectroscopy measurements. Irradiations were performed at room temperature using a Sr-90/Y-90 beta source of the Riso TL reader (dose rate = 10 mGy/s). TL measurements were made at 5 degrees C/s within the dose range from 1 to 50 Gy. The glow curve consists of a dominant peak at 350 degrees C and three additional peaks at 110, 160 and 280 degrees C. Results showed that the TL signal increases linearly with beta irradiation dose. Our results suggest that Fe and Cr ions together with the presence of secondary phases such as mica and apatite play important roles in the TL process. Based on the linearity of the TL response, we conclude that alexandrite shows potential for use in dosimetry. (AU)

• Processo FAPESP: 10/16437-0 - Caracterização e aplicações de materiais dosimétricos utilizando a luminescência opticamente estimulada e técnicas complementares
• Beneficiário: Linda Viola Ehlin Caldas
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/22984-0 - Process Mineralogy '17
• Beneficiário: Neilo Marcos Trindade
• Modalidade de apoio: Auxílio à Pesquisa - Reunião - Exterior