High-Frequency Region of the Spectrum of Electron and Positron Bremsstrahlung

The cross section for a bremsstrahlung process in which almost all the energy of an incident high-energy electron is transferred to the photon is calculated analytically, using techniques previously developed for atomic photoeffect. Only terms of relative orders $a^4$, $a^2{q}^2$, and $q^4$ are neglected, where $a\equiv Z{e}^2$ and $q$ is the momentum of the outgoing low-energy electron (with $\hslash =c=m_e=1\mathrm{}$). Similar results are obtained for positron bremsstrahlung and pair production; previous work on the photoeffect is extended. The accuracy of these predictions is discussed, and they are compared with experiments.