The Use of Alanine as a Solid Dosimeter

Electron spin resonance has been found to be a satisfactory technique for the calibration and measurement of radiation doses by means of alpha - alanine dosimeters. Powdered alpha -alanine dosimeters have been calibrated for the measurement of doses from gamma -, BETA -, proton, and x radiation in the range of l00 r to beyond l0/sup 5/ r. At low doses there are measurable differences in the number of free radicals created by each of the various types of radiation. The alpha alanine is less sensitive to x rays than to the gamma - rays, electrons, or protons studied so far. Plastic holders are satisfactory for measuring doses above l000 r. Below 1000 r, better results are obtained with glass holders. However, selected quartz is to be preferred for general usage because of freedom from residual signals. Further studies in this laboratory are being conducted with quartz holders designed for optimum sensitivity. For some dosemeters, Teflon holders are recommended, since the ma terial itself can be made into a possible dosimeter also. Dosimeters from alpha -alanine were found to be stable, having about 5% decay after 90 days. (auth)