▎ 摘　　要

Photon-energy dependent photoemission experiments using high harmonic radiation as a tunable photon source on epitaxially grown graphene on a Ni(111) substrate are presented. A resonance in the photoemission cross section for the sigma and pi states of graphene was observed and compared to a simple model for the determination of photoemission cross sections of free standing graphene, pointing out the role of the interaction of graphene with the nickel substrate.