Leitfähigkeit von Hexan bei Einwirkung von Y-Strahlen und ihre Bedeutung für die Dosimetrie

Abstract

The influence of primary and secondary recombination on the γ-ray-induced conductivity of liquid n-hexane is studied experimentally and theoretically. Conductivity measurements were made with a parallel-plate ionization chamber, varying the electrical field, the electrode distance and the dose rate. The primary recombination can be explained with a theory developed by ONSAGER for the recombination of single ion pairs in dense gases, whereas JAFFE’S theory of column ionization is not applicable. Independent of the ion mobilities, for hexane in absence of an electric field a G-value of 0,13 ± 0,01 for the ion pairs escaping primary recombination is obtained; this corresponds to a mean escape probability of 3% and a mean effective initial distance of the ions in an ion pair of 80 mµ. Finally, the applicability of liquid-filled ionization chambers for dosimetry is discussed.