Typical experimental arrangement for time-resolved XAS
in a pump-probe scheme with excitation (pump) of the
sample by on optical laser (Ti:sapphire and optical parametric
amplifier, OPA) and probing the state of the sample with x-ray
pulses from the storage ring at defined time delays. [Taken from
Wernet et al., Appl. Phys. A 92, 511 (2008)].

Femtosecond time-resolved X-ray Absorption Spectroscopy (fs-XAS) is uniquely suited to follow in real time of atomic motions the combination of electronic and geometric structure evolution during ultrafast processes such as chemical reactions, phase transitions and magnetism dynamics.

Femtosecond tuneable soft x-ray pulses are generated at the FEMTOSPEX facility and three end stations can be used to study samples in various environments such as solids, magnetic samples (IGAMA link to FemtoslicingMagnetism) and liquid samples.