POLARIZATION OF BREMSSTRAHLUNG AT SHORT-WAVELENGTH LIMIT

The polarization of bremsstrahlung at the short-wavelength limit is calculated by means of Sommerfeld-Maue wave functions, i.e., for low atomic numbers. The two-component spinor representation is used to obtain the correlations between the spins of the initial and final electron and the photon polarization vector. Formulas are given for the circular and linear polarization of bremsstrahlung summed over the spin directions and integrated over the angles of the final electron, the incoming electron being longitudinally or transversely polarized. The photon polarization from unpolarized electrons is derived. Finally, comparison with Born-approximation calculation is made and numerical results are shown. The agreement with experimental data is not very satisfactory; it is probably due to the fact that experiments are not performed directly at the short-wavelength limit. © 1969 The American Physical Society.