Abstract:

Fossil remains, which provide important information about past life and ecology, are especially important in natural history and life evolution. Recently, many interdisciplinary dating studies have been conducted and many different techniques have been used to investigate the data obtained in this field. Electron Spin Resonance (ESR) (or alternatively, Electron Paramagnetic Resonance, EPR) is one of the methods used in absolute dating and dosimetry studies. It is based on determination of the radiation-centered radicals obtained from the radiation dose absorbed by irradiated materials. One of the important problems in dosimetry and dating studies performed with ESR method is the dependence of experimental parameters on the accumulated dose. The accumulated dose value is effective in determining the actual result of the dating and dosimetric samples. This value is influenced from the stability of the ESR centers, experimental stages, sample preparation or measurement processes. In this study, how the modulation amplitude parameter affects ESR signal intensity in ESR dating and dosimetry studies of tooth enamel investigated. The selective archaeological animal tooth enamel sample was used from the archaeological site of Köşk Höyük, in Turkey for experimental studies. This sample was prepared with combined processes of mechanical and chemical treatment of tooth in laboratory. Tooth enamel sample was irradiated by 60Co gamma-ray source in dose of 1000 Gy at Çekmece Nuclear Research and Training Center (ÇNAEM), Turkey. After irradiation, ESR spectra were recorded at different modulation amplitude values at room temperature using X-band ESR Spectrometer. According to the results obtained, the most suitable modulation amplitude values for ESR measurements of tooth enamel sample examined in the study was found between 0.25G and 2G.

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