Energetic photoionization spectroscopy in the configuration space for atom-fullerene endohedral compounds*

In the photoionization of an atom confined in a fullerene the electrons directly ionized from the atom partly reflect at the cage. The delocalization of outer atomic electrons also leads to significant collateral emission from the cage site [1]. On the other hand, the atom-fullerene hybrid electrons emanate in a channel with roughly equal mix of dual character. Further, the low angular momentum fullerene electrons, that see weaker centrifugal barrier potential, emerge by a unusual ionization pathway, originating from the interior Coulomb region [2]. The interference among these amplitudes produces distinct oscillation patterns in the cross sections at energies higher than the plasmon energy region. It is shown that the transformation of a subshell cross section to the radial co-ordinates uniquely identifies the electron emission site in the compound. Results are presented for Xe@C$_{60}$.\\[4pt] [1] McCune et al., \textit{Phys. Rev.} A \textbf{80}, 011201(R) (2009)\\[0pt] [2] Hopper et al., \textit{J. Phys.} B (submitted).