When studying the dynamics of atomic processes, the analysis of polarization phenomena allows unique insights. In the range of hard X-rays, conventional polarization methods fail due to the high photon energies. This is remedied by the Compton effect, whose scattering distribution exhibits strong polarization sensitivity.
In order to use the Compton effect to study polarization properties, special segmented semiconductor detectors were developed in collaboration with the GSI Helmholtzzentrum für Schwerionenforschung GmbHExternal link in Darmstadt and the FZ JülichExternal link. Due to the strip geometry of the detector crystals, a simultaneous spatially resolved and energy resolved measurement of incident photons is possible.
In addition to the simple absorption of incident radiation, Compton scattering of photons in the detector crystal can also occur, in which part of the photon energy is transferred to an electron of the detector crystal. If both the electron and the Compton-scattered photon are detected in the detector, the scattering distribution can be reconstructed if there is a sufficient number of such events, which provides information about the polarization properties of the incident radiation.
References
[1] U. Spillmann et al., Rev. Sci. Instrum. 79, 083101 (2008)External link
[2] G. Weber et al., J. Phys.: Conf. Ser. 583, 012041 (2015)External link
[3] M. Vockert et al. Nucl. Instrum. Methods Phys. Res., Sect. B 408, 313 (2017)External link