  Angle-resolved photoelectron spectroscopy is an extremely powerful probe of
materials to access the occupied electronic structure with energy and momentum
resolution. However, it remains blind to those dynamic states above the Fermi
level that determine technologically relevant transport properties. In this
work, we extend band structure mapping into the unoccupied states and across
the entire Brillouin zone by using a state-of-the-art high repetition rate,
extreme ultraviolet fem- tosecond light source to probe optically excited
samples. The wide-ranging applicability and power of this approach are
demonstrated by measurements on the 2D semiconductor WSe2, where the
energy-momentum dispersion of valence and conduction bands are observed in a
single experiment. This provides a direct momentum-resolved view not only on
the complete out-of-equilibrium band gap but also on its renormalization
induced by electron-hole interaction and screening. Our work establishes a new
benchmark for measuring the band structure of materials, with direct access to
the energy-momentum dispersion of the excited-state spectral function.
