Stimulated luminescence properties of natural alexandrite in response to X-ray irradiation

Author(s)

Silva, A. O. ; Amorim, Y. F. ; Nunes, M. C. S. ; Ulsen, C. ; Yoshimura, E. M. ; Trindade, N. M.

• Document type: Journal article
• Source: Journal of Luminescence; v. 269, p. 7-pg., 2024-02-10.

Abstract

This paper reports for the first time the in-depth study of thermoluminescence (TL) and optically stimulated luminescence (OSL) of Brazilian alexandrite pellets (BeAl2O4: Cr3+) previously exposed to X-rays. Firstly, structural and composition analysis of alexandrite powder was performed to verify the quality of the samples. Xray diffraction (XRD) pattern revealed that the sample is composed by chrysoberyl (alexandrite) and minor phases as quartz, kaolinite and phlogopite. The presence of several elements, including Cr and Fe, was also detected by X-ray fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Alexandrite pellets exhibited an intense TL signal when previously irradiated with X-ray, showing from the deconvolution five glow peaks centered at 75, 130, 175, 250 and 300 C-degrees. The activation energy (E) and frequency factor (s) were estimated using first-order and general-order kinetic equations. The deconvolution of the OSL curve for alexandrite fit reasonably into three components, characterized as fast, medium and slow. The results obtained showed that the OSL and TL signals of alexandrite pellets vary linearly as a function of the X-ray. The pellets have low fading at room temperature, maintaining 63% of the OSL signal after 10 days of sample storage. Overall, the results suggest that natural alexandrite has TL and OSL sensitivity to X-ray radiation, being a promising material to this radiation. (AU)

• FAPESP's process: 20/15626-6 - Study of the optical and thermoluminescent properties of Brazilian alexandrites
• Grantee: Alexia Oliveira Silva
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 18/05982-0 - R&D&I in radiation metrology in the health area
• Grantee: Linda Viola Ehlin Caldas
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 22/14516-8 - Study of mechanisms of luminescence in alexandrite pellets using optically stimulated luminescence
• Grantee: Matheus Cavalcanti dos Santos Nunes
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• FAPESP's process: 23/04955-7 - Investigation of phototransferred thermoluminescence in Alexandrite pellets
• Grantee: Alexia Oliveira Silva
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• FAPESP's process: 19/05915-3 - Characterization of minerals for luminescent dosimetry of ionizing radiations
• Grantee: Neilo Marcos Trindade
• Support Opportunities: Regular Research Grants
• FAPESP's process: 22/06690-8 - Investigation of optically stimulated luminescence (OSL) of alexandrite pellets previously exposed to X-rays.
• Grantee: Yasmim Freire Amorim
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 21/12758-1 - Development and characterization of an optically stimulated luminescent detector based on natural Brazilian alexandrite
• Grantee: Matheus Cavalcanti dos Santos Nunes
• Support Opportunities: Scholarships in Brazil - Master