Spatial Distribution of Photoelectrons Produced by X-rays

Abstract

JUDGING from recent papers on this subject, there seems to be considerable diversity of opinion concerning the explanation of the dispersion or ‘spread’ of the photoelectrons, whilst there appears to be no disagreement about the cause of the longitudinal asymmetry, which is generally assumed to correspond to the transfer to the photoelectrons of the momentum of the absorbed radiation. J. M. Nuttall, H. S. Barlow, and the present writer (hereinafter referred to as N.B.W.) recently investigated the longitudinal distribution of photoelectrons, and the results (not yet published) indicate an average forward component of momentum of the photoelectrons which is appreciably greater than the momentum, hv/c, of an incident quantum. The writer has also made a closer quantitative study of the results of other observers, and finds that with the exception of P. Auger's results an ‘excess asymmetry’ is revealed in each case. As regards dispersion, experimental results seem to prohibit all theories except one, with which there is fair agreement.