ESR study of elephant tooth enamel from the Kärlich-Seeufer site in Germany

Enamel from 6 different positions in a well preserved elephant tooth from the Kärlich-Seeufer site in Germany has been irradiated up to 32 kGy. The X-band (v = 9.5 GHz) ESR spectra of two subsamples have been decomposed into three real components with Maximum Likelihood Common Factor Analysis (MLCFA). One of these components due to orthorhombic CO2- radicals is predominant. Dose response curves for the contributions of these MLCFA components and for different heights in the ESR spectra have been obtained and fitted with different models. Depending on the model, the equivalent dose for the preferably used height at g = 1.9973, due to CO2-, ranges from 70 to 130 Gy. Due to a very low uranium and thorium content in both enamel and dentine (< or = approximately 10 ppb) and to an important external y-attenuation, the ages fluctuate between 300 and 575 ka.