Formation of metal colloids in ionic crystals by electron irradiation and its application to high-level dosimetry

Metal colloids formed after electron irradiation in ionic crystals were examined with the aim to use them for evaluation of high-level radiation dose. Optical absorption band of Na-colloids in NaCl was most useful for the measurement among that of several kinds of ionic crystal examined. Photoacoustic spectroscopy (PAS) was newly used for estimation of the Na-colloids in NaCl. A good response of the PAS signal to the number of electron pulses was obtained in the range from 107 to 109 Gy. It was also shown that thermal annihilation of the colloids yields a thermoluminescence glow peak which may also provide a useful method for high-level radiation dose. (author)