Two-photon bremsstrahlung

We present a calculation of the cross sections for two-photon bremsstrahlung in a Coulomb potential. The calculation was done in second-order nonrelativistic perturbation theory and in the dipole approximation. The potential was taken into account exactly by using the Coulomb Greens function. The matrix element was integrated analytically as far as possible and then computed numerically quite accurately. Limiting cases are discussed. Results are presented here for a special emission geometry. These are compared with the recent experiment of Altman and Quarles, and large discrepancies are found.