Fig. 5
From: Symmetry breakdown of electron emission in extreme ultraviolet photoionization of argon
Front view of spectrometer setup with angle-resolved intensity distribution. Front view of the spectrometer setup and its 16 individual devices together with an exemplary angular distribution pattern of neutral argon ionization at 51 eV photon energy. The data points (blue) are transmission-calibrated raw data in the spectrometer plane of the experiment as depicted in Fig. 4, that is 38.2° rotated with respect to the dipole plane. The black curve is a fit based on Eq. (1). The center of the inner ring is the interaction zone where argon atoms are interacting with the FEL photons
