Polarization studies on the radiative recombination of highly charged bare ions

Abstract

The polarization of the emitted photons is studied for the radiative recombination of free electrons into the bound states of bare, highly charged ions. We apply density matrix theory in order to investigate how the photon polarization is affected if the incident electrons are themselves spin polarized. For K-shell electron capture, for instance, the linear polarization of the light, which is measured out of the reaction plane, is defined by the degree of polarization of the electrons and may be used as a tool for studying the polarization properties of the electron targets and/or the projectile ions. Detailed computations of the Stokes parameters of x-ray emission following the radiative recombination of bare uranium ions ${\mathrm{U}}^{92+}$ are carried out for a wide range of projectile energies and for different polarization states of the incident electrons.