Multiple Disintegration Processes Produced by Cosmic Rays

Abstract

SOME months ago, in collaboration with D. L. Livesey and L. V. Chilton¹, we-described experiments on the prototype of the new photographic emulsions for the detection of fast protons and other heavy particles, which are now being produced by Ilford, Ltd., in various types and which are referred to as 'Nuclear Research Emulsions'. Our experience with these plates strongly suggested that they would be very suitable for detecting the multiple disintegration phenomena produced by the fast neutrons, ?-rays and other radiations in the cosmic rays^2,3,4,5. We therefore exposed plates for six weeks at the Pic du Midi, Hautes Pyrenées, at a height of 3,800 metres, and in this communication we wish to direct attention to the important conclusions which can be drawn from an examination of the experimental material thus obtained.