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After a brief introduction to x-ray-induced processes anx-ray free-electron lasers, results from some of the first experiments carried out at the world's first x-ray free-electron laser, the Linac Coherent Light Source at SLAC National Accelerator Laboratory, will be presented and compared with theory. It will be shown that the x-rays from the LCLS are so intense that (a) an atom can be completely stripped of all its electrons; (b) inner-shell ionization can be as fast as the Auger decay of an inner-shell hole, thus leading to the efficient formation of double-core-hole states; and (c) the characteristics of the Auger decay process itself can be modified. In applications to heavy atomic species, the role of deep-inner-shell decay cascades will be elucidated. Specifically, these decay cascades are partly responsible for the extremely high charge states detected in LCLS experiments on atomic xenon. Finally, ultrafast x-ray scattering from an electronic wave packet will be discussed. It will be seen that the corresponding scattering patterns differ dramatically from those obtained with the coherent-scattering theory for stationary systems using the time-dependent electron density. |