Photoelectron imaging of helium droplets.
The photoionization and photoelectron spectroscopy of He nanodroplets (10(4) atoms) has been studied by photoelectron imaging with photon energies from 22.5-24.5 eV. Total electron yield measurements reveal broad features, whose onset is approximately 1.5 eV below the ionization potential of atomic He. The photoelectron spectra are dominated by very low energy electrons, with <E(k)> less than 0.6 meV. These results are attributed to the formation and autoionization of highly vibrationally excited He(*)(n) Rydberg states within the cluster, followed by strong final state interactions between the photoelectron and the droplet.
Peterka
Darcy S
DS
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Lindinger
Albrecht
A
Poisson
Lionel
L
Ahmed
Musahid
M
Neumark
Daniel M
DM