The Compton Effect and Polarisation

Abstract

WHEN a beam of X-rays passes through a medium, three kinds of phenomena may be observed: the photoelectric effect, the Compton effect, and the socalled classical scattering. The conversion of the number of recoil and photoelectrons made by means of the Wilson expansion chamber by A. H. Compton and D. Skobeltzin showed that the probability of the Compton effect greatly increases as the wave-length decreases. On the other hand, the intensity of the scattered radiation does not depend upon the wavelength of the incident X-rays. It may be expected from this that where hard X-rays are used, the modified rays will be predominant, whereas in the case of soft X-rays (Barkla's experiments) the scattered radiation will consist almost entirely of the unmodified rays (classical scattering).