  Electronic Coulomb correlations lead to characteristic signatures in the
spectroscopy of transition metal pnictides and chalcogenides: quasi-particle
renormalizations, lifetime effects or incoherent badly metallic behavior above
relatively low coherence temperatures are measures of many-body effects due to
local Hubbard and Hund's couplings. We review and compare the results of
angle-resolved photoemission spectroscopy experiments (ARPES) and of combined
density functional dynamical mean field theory (DFT+DMFT) calculations. We
emphasize the doping-dependence of the quasi-particle mass renormalization and
coherence properties.
