Temperature and frequency effects in tooth enamel electron spin resonance dosimetry

Electron spin resonance of CO33- molecule ions in human tooth enamel have been studied at various temperatures between 4 and 350 K and at various microwave powers in the 9 GHz (X) band. Signal saturation during cooling due to slowing down of the electron spin relaxation has been established. The 35 GHz (Q) band spectra of tooth enamel, irradiated with various γ-ray doses, are also presented. Q band ESR dosimetry offers some advantages over the X-band dosimetry due to signal enhancement from the spin level population difference and especially due to a better filling factor which is important when only minute quantities (a few mg) of enamel are available. (author)