OPTICAL OBSERVATION OF SELF-QUENCHING STREAMERS BY ALPHA-RAYS AND BETA-RAYS

Optical images of self-quenching streamers (SQSs) in a gas counter hav e been observed for alpha- and beta-ray, incident charged particles. I ndividual images of the streamers were obtained by using an image-inte nsifier system with a gating function. The observation was performed f rom the axial direction of the gas counter used. For alpha-ray irradia tion, streamers develop only in two specific directions orienting prim ary-ionization tracks formed by alpha-rays. On the other hand, for bet a-ray, streamers grow in various directions; obtained images are simil ar to those for X-ray. On the basis of the observation, SQS-formation mechanisms by different sorts of ionizing radiation are discussed. A p ossible mechanism of ''PRimary-Ionization Track ORiented (PRITOR) type SQS'' induced by alpha-ray is proposed.