2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/20138Fundamental principles of mapping 3-dimensional quasiparticle dispersions in the valence band using angle-resolved photoemission spectroscopy are discussed. Such mapping is intrinsically limited in accuracy owing to damping of the final states, resulting in equivalent broadening in the surface-perpendicular wavevector. Mechanisms of the intrinsic accuracy are discussed in depth based on a physically transparent picture involving interplay of the final- and initial-state spectral functions, and illustrated by photoemission simulations and experimental examples. Other interesting effects of 3-dimensional dispersions include 'ghost' peaks in the unoccupied valence band region and finite peak width at the Fermi level. Finally, optimization of the experiment on the intrinsic accuracy is discussed.9 pages, 6 Postscript figures, minor revisions, J. Electr. Spectr. Relat. Phenom. (in press)Strongly Correlated Electronstext