  We study the role of electron-electron correlation in the ground-state of Ne,
as well as in photoionization dynamics induced by an attosecond XUV pulse. For
a selection of central photon energies around 100 eV, we find that while the
mean-field time-dependent Hartree-Fock method provides qualitatively correct
results for the total ionization yield, the photoionization cross section, the
photoelectron momentum distribution as well as for the time-delay in
photoionization, electron-electron correlation is important for a quantitative
description of these quantities.
