Theory of Bremsstrahlung and Pair Production. II. Integral Cross Section for Pair Production

The differential cross section for bremsstrahlung and pair production at high energies obtained in the preceding paper by Bethe and Maximon has been integrated over all angles, and formulas are given for the integral cross section for all Z For small Z the correction to the Born approximation is proportional to {Z}^{2} and the constant of proportionality is given. The correction for heavier elements is somewhat less than the {Z}^{2}..