  We report on the first demonstration of femtosecond xray absorption
spectroscopy. Our experiments are made possible by the use of broadly tunable
bending-magnet radiation from laser-sliced electron bunches within a
synchrotron storage ring. We measure ultrafast electronic dynamics associated
with the photo-induced insulator-metal phase transition in VO2. Symmetry and
element specific xray absorption from near 500 eV V2p and O1s core levels
separately measures the filling dynamics of differently hybridized V3d O2p
electronic bands near the Fermi level.
