Production of Positive Electrons by Β-Particles

Abstract

IN a previous note1 we described some experiments carried out with a weak source of radium placed inside an expansion chamber, and showed that the ordinary-radiation is accompanied by an emission of positrons. It is quite impossible to ascribe the origin of these positive electrons to the internal conversion of rays or to any other known mechanism by which positively charged particles are created. It seemed to us to be most plausible to assume that the appearance of these positively charged particles is closely connected with the phenomenon of disintegration. However, more recent experiments have shown that the number of positrons depends to a large extent upon the nature of the walls surrounding the source examined.