Thermoluminescence of rose quartz from Minas Gerais, Brazil

Author(s)

Martins, R. T. E. K. ; Ferreira, I. A. ; Silva, A. O. ; Nunes, M. C. S. ; Ulsen, C. ; Kunzel, R. ; Souza, M. M. ; Chithambo, M. L. ; Yoshimura, E. M. ; Trindade, N. M.

• Document type: Journal article
• Source: Radiation Physics and Chemistry; v. 209, p. 11-pg., 2023-04-15.

Abstract

This article reports the thermoluminescence (TL) properties of rose quartz from Minas Gerais (Brazil), a trans-lucent pink variety of quartz. Firstly, the sample shows a pure alpha-quartz phase, based on X-ray diffraction results. Also, the mineral shows a wide optical absorption band at about 500 nm, typical of rose quartz. In addition, X-ray fluorescence showed a high percentage of purity (99.1% of the SiO2) , the inductively coupled plasma optical emission spectrometry (ICP OES) recorded the presence of elements such as Al, Ca, Fe , Ti. The TL mea-surements were carried out using a commercial Riso TL/OSL reader, model DA-20, equipped with a built in 90Sr/90Y beta source, used to irradiate the sample to different radiation doses (0.01 - 1Gy). The glow curve, measured at a heating rate of 1 K/s, consists of a prominent peak at 355 K followed by other low intensity peaks at higher temperatures. Measurements of the main peak are reproducibility with a coefficient of variation (C.V.) of-1.3% and a repeatability of-1.8%. Kinetic analysis of the main peak was carried out using experimental methods comprising Tm-Tstop technique, the initial rise method, peak shape estimation and various computational methods (TGCD, TLanal, TLDecoxcel and GlowFit). The peak obeys first order kinetics, with activation energy of 0.86 eV, and a frequency factor of the order of 1011 s- 1. Finally, in the dose range studied, the peak shows a sublinear dose response after which supralinearity sets in. (AU)

• FAPESP's process: 21/05042-0 - Characterization of the optical and thermoluminescent properties of quartz from the south of Minas de Gerais (Brazil)
• Grantee: Isabela Alves Ferreira
• 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: 21/10117-9 - Computed tomography in paediatric patients: new strategies for radiation dose and image quality optimization
• Grantee: Marcelo Baptista de Freitas
• Support Opportunities: Regular Research Grants
• FAPESP's process: 22/07200-4 - Characterization of the optical and thermoluminescent properties of amazonites.
• Grantee: Roberto Turibio Ebina Kawanaka Martins
• 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
• 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: 19/05915-3 - Characterization of minerals for luminescent dosimetry of ionizing radiations
• Grantee: Neilo Marcos Trindade
• Support Opportunities: Regular Research Grants