  We present the first measurements of photoelectron spectra of atomic clusters
embedded in superfluid helium (He) nanodroplets. Owing to the large absorption
cross section of xenon (Xe) around 100 eV photon energy (4d inner-shell
ionization), direct dopant photoionization exceeds charge transfer ionization
via the ionized He droplets. Despite the predominant creation of Xe^2+ and
Xe^3+ by subsequent Auger decay of free Xe atoms, for Xe embedded in He
droplets only singly charged Xe_k^+, k=1,2,3 fragments are observed. Broad Xe^+
ion kinetic-energy distributions indicate Coulomb explosion of the ions due to
electron transfer to the primary Auger ions from surrounding neutral atoms. The
electron spectra correlated with Xe ions emitted from the He nanodroplets
contain a low-energy feature and nearly unshifted Xe photolines. These results
pave the way to extreme ultraviolet (XUV) and x-ray photoelectron spectroscopy
of clusters and molecular complexes embedded in He nanodroplets.
