Decomposition of the laboratory gamma irradiation component of angular ESR spectra of fossil tooth enamel fragments
Date
2010
Authors
Joannes-Boyau, Renaud
Grun, Rainer
Bodin, Thomas
Journal Title
Journal ISSN
Volume Title
Publisher
Pergamon-Elsevier Ltd
Abstract
Spectrum decomposition of the angular measurements of fossil tooth enamel fragments using an automated simulated annealing (SA) procedure shows that the mix CO2- radicals generated by laboratory irradiation is significantly different to that of the natural sample. The naturally irradiated sample contains about 10% of non-oriented CO2- radicals and a mix of 35:65 orthorhombic to axial CO2- radicals. In contrast, laboratory irradiation generated about 40% of non-oriented radicals and a large amount of orthorhombic CO2- radicals, while we failed to detect any axial CO2- radicals. The results indicate that geological aging of the sample incurs various annealing and transfer processes; their precise nature is yet unknown. Nevertheless, the understanding of the formation and transfer processes that leads to the observed mix of CO2- radicals in fossil tooth enamel is essential for the reliable application of ESR dating.
Description
Keywords
Keywords: ESR spectra; Fossil tooth enamel; Gamma irradiation; Irradiated samples; Non-oriented; Spectrum decomposition; Transfer process; Electron spin resonance spectroscopy; Irradiation; Ocean habitats; Simulated annealing; Carbon dioxide; carbon dioxide; carbon CO - 2 radicals; Enamel fragment; ESR dating
Citation
Collections
Source
Applied Radiation and Isotopes
Type
Journal article
Book Title
Entity type
Access Statement
License Rights
Restricted until
2037-12-31
Downloads
File
Description