Photoemission along the surface normal of Cu-001- - Experiment and theory

Experimental normal photo-emission spectra from Cu(100) were taken with linearly polarised synchrotron radiation at photon energies between 13 and 48 eV and at two different angles of light incidence. They are compared with intensity profiles calculated by non-relativistic "one-step-model" theory including a classical macroscopic radiation field inside the crystal. All direct transition features of the spectra are reproduced quite well, while agreement in detail is not yet perfect. Several possibilities for improving the agreement are discussed.