ED-XRD/XRF: archaeometry applications

• Grant number: 17/09093-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: August 01, 2017
• End date: January 31, 2022
• Field of knowledge: Physical Sciences and Mathematics - Physics
• Principal Investigator: Manfredo Harri Tabacniks
• Grantee: Hellen Cristine Santos Zagatto
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 17/07366-1 - Collect, identify, describe, exhibit: the curatorial cycle and the production of knowledge, AP.TEM

Abstract

Combining a conventional rotating anode Cu X-ray source and assembling a single X-ray detector on a computer controlled XY stage, a proxy of an imaging X-ray detector was constructed for the measurement of simultaneous EDXRD (Energy Dispersive X-Ray Diffraction) and EDXRF (Energy Dispersive X-Ray Fluorescence) of the same spot of a sample. The main advantages of this setup are the virtual no need for sample preparation, and the simultaneous XRF-XRD measurements of the same spot, enabling a combined and consistent analysis of a sample, and characterizing both the chemical elements and their crystalline structure. The time consumed in an analysis using this setup is large due to the need of acquiring multiple (several hundred) single spectra, which can be compensated, by using a variable acquisition time, depending on the count rate, exploring the high dynamic range of the X-ray emission during data acquisition. A Python code was written for offline data filtering and analysis. Using a simple geometrical model, d-spacings were calculated and the model predictions were superimposed to the ED (Energy Dispersive) surface plots with good agreement. The instrument proved to work according to expectations, obtaining interplanar distances (d) and chemical identification of samples simultaneously and helped to define the main experimental parameters (reference angle, sample-detector distance and acquisition time) and measurement protocols. The next step, the main objective of this project, is to apply this system to study archaeological ceramics. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SANTOS, HELLEN C.; SILVA, TIAGO F.; LEITE, ALISSON R.; ASSIS, RENAN F.; CAMPOS, PEDRO H. O. V.; RIZZUTTO, MARCIA A.; TABACNIKS, MANFREDO H.. Characterization of a system that combines energy dispersive X-ray diffraction with X-ray fluorescence and its potential applications in archeometry. Journal of Applied Physics, v. 126, n. 4, JUL 28 2019. (17/09093-2)

LINARES, R.; FONSECA, L. M.; SANTOS, H. C.; ADDED, N.; SEABRA, C. C.; XING, Y. T.. Assessing the potentiality of the 250kV-SSAMS for stopping power measurements at low energies. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SP, v. 945, NOV 21 2019. (17/09093-2)

SANTOS, HELLEN CRISTINE; CALIRI, CLAUDIA; PAPPALARDO, LIGHEA; RIZZO, FRANCESCA; ROMANO, FRANCESCO PAOLO. MA-XRF and XRD analysis revealing a polychrome Centuripe vase. JOURNAL OF ARCHAEOLOGICAL SCIENCE-REPORTS, v. 35, FEB 2021. (17/09093-2)

DOS SANTOS, HELLEN CRISTINE; CALIRI, CLAUDIA; PAPPALARDO, LIGHEA; CATALANO, ROBERTO; ORLANDO, ANDREA; RIZZO, FRANCESCA; ROMANO, FRANCESCO PAOLO. Real-time MA-XRF imaging spectroscopy of the Virgin with the Child painted by Antonello de Saliba in 1497. Microchemical Journal, v. 140, p. 96-104, JUL 2018. (17/09093-2)