Ionization mechanisms of C60 molecules irradiated by a short intense 800-nm laser pulse are studied. Angle- resolved photoelectron spectra show above-threshold ionization (ATI) patterns with a low peak contrast and a remarkably smooth angular distribution. The results are interpreted by combining two theoretical models. A time-dependent Schr¨ odinger equation (TDSE) calculation based on the B-splinemethod that explicitly takes into account the molecular potential mimics the single-active-electron response while a statistical model accounts for the many-electron effects.We show that the latter are responsible for the loss of contrast in the ATI peaks. The smooth angular distribution arises in the TDSE calculation as a result of the high angular momentum of the C60 ground electronic state and therefore is a manifestation of the atomic behavior of the molecule.
|Journal||Physical Review A. Atomic, Molecular and Optical Physics|
|Publication status||Published - 3 Jul 2013|