Radiation arising from the Mutual Annihilation of Protons and Electrons

Abstract

THE recent work of Millikan (Science, 62, 444, 1925) has added to our list of radiations, some of far shorter wave-length than any hitherto discovered. By extrapolation of A. H. Compton's formula for absorption (Phys. Rev., 21, 483, 1923), it has been estimated that these new rays have a range of wave-lengths between 0.0004 and 0.00067 Ångström. (Had the analogous formula developed by Jauncey (Phys. Rev., 22, 233, 1923) been used, the values would have been between 0.0022 and 0.0029.) It is suggested in Millikan's article that “the computed frequencies of these rays also correspond closely to the energy involved in the simple capture of an electron by a positive nucleus”.