Ultrafast X-ray science at the Advanced Light Source

Summary form only given. An important frontier in ultrafast research is the application of femtosecond X-ray pulses to investigate structural dynamics associated with phase transitions in solids, chemical reactions and rapid biological processes. The fundamental time scale for such processes is an atomic vibrational period, /spl sim/100 fs. Since X-rays interact with core electronic levels they can provide direct information about atomic structure. X-ray diffraction, extended X-ray absorption fine structure (EXAFS) and related X-ray techniques are widely used at modern synchrotrons providing high-brightness X-ray beams. However, the time resolution available from synchrotrons is nearly three orders of magnitude too slow to probe atomic motion within a single vibrational period. We have recently generated femtosecond synchrotron pulses from the Advanced Light Source (ALS) using ultrashort pulses. Future plans for developing femtosecond X-ray science at the ALS will be discussed.