Electron bremsstrahlung angular distributions in the 1-500 keV energy range

Predictions of bremsstrahlung angular distributions from incident electrons of kinetic energy 1-500 keV are examined using numerical data obtained from a numerical calculation in partial waves, under the assumption that the process is described as a single-electron transition in an atomic central potential. For low-$Z$ elements the Born approximation or the Elwert-Haug approach, modified with form-factor screening, give good predictions for the shape of the angular distributions, except at forward and backward angles. That is, the results are good in the main region which contributes to the energy spectrum. For high-$Z$ elements such predictions are accurate within about 15%. Analytic properties of the shape of the angular distribution from simpler theories suggest a simple way to parametrize the results.