TEMPERATURE AND FREQUENCY-EFFECTS IN TOOTH ENAMEL ELECTRON-SPIN-RESONANCE DOSIMETRY

Electron spin resonance of CO33- molecule ions in human tooth enamel h ave been studied at various temperatures between 4 and 350 K and at va rious 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 w ith various gamma-ray doses, are also presented. Q band ESR dosimetry offers some advantages over the X-band dosimetry due to signal enhance ment 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.