Fig. 4: The experimental results induced by the electron impact ionisation.
a Measured distribution of (θcm-KER) for three-body CE induced by the electron impact ionisation. Three components marked with grey solid circles with high-KER originate from the vertical triple ionisation process. One low-KER component marked with red solid circle stand for the three-body CE induced by the inner-shell ionisation process followed by Auger decay. b Simulated distributions of θcm vs KER for the four components marked in (a), which comes from three-body CE induced by the ionisation of both valence and inner-shell electrons. c Schematic plot for the relaxation mechanism for the inner-shell ionisation and Auger decay. Two 2a1 electrons are kicked out by the incident electrons, and after the ultrafast nuclear relaxation, two 1b1 electrons filled the double holes, and the third electron is ionised by absorbing the radiation. d The potential energy curves for the involved electronic states of trication and autoionisation state of dication. The instant of the Auger ionisation is indicated by the vertical blue arrow after ultrafast nuclear relaxation along the autoionisation state.
