Etude des noyaux de condensation radioactifs de l'atmosphère

Abstract

A comparative study has been made between the Radon and Thoron decay products in the atmosphere, by means of α radiation counting, using Zeleny tubes, a diffusion battery, or paper or membrane filters for sample collection. Some of the characteristic properties of the radioactive ions are studied with mobilities above 10−3 cm2 sec−1 V−1, radius below 2·10−6 cm. Neutral radioactive condensation nuclei are measured by means of a diffusion battery. The average air concentrations of Radon and Thoron are determined. The results indicate that for the Radon daughters, as well as the Thoron daughters, about 42% of the total α activity is found on particles having a radius less than 2·10−6 cm. A theoretical discussion of the experimental results is made.DOI: 10.1111/j.2153-3490.1966.tb00275.x