Pair Production by Photons

This paper reviews, analyzes, and integrates the various quantitative results that have been obtained for the process of pair production by photons. Included in this summary is a detailed review of total and differential cross sections for pair production in an atomic and in an electron field, with a critical evaluation of the conditions of validity and the accuracy of the results. In addition, a summary is given of the important kinematic relations, theoretical considerations, and the polarization effects that occur in pair production. The paper does not include a treatment of radiative corrections to pair production, thick-target pair production, or pair production by electrons in the field of a nucleus (trident production). Otherwise, the review is intended to include results on pair production available up to January 1969.