Photon-atom interaction processes relevant to data obtained with high-power lasers and synchrotron light sources will be investigated. In most cases the dynamics of the processes considered will be governed by electron correlation effects. Studies will be carried out within the framework of a variational principle for Nth pertubative processes. Interactions to be investigated include multiphoton ionization of various atoms (including atomic hydrogen, alkalis, rare gases and negative halogen ions) and photoionization of open shell atoms (including atomic oxygen and chlorine).
