9313735 DESHMUKH Description: This research proposes a series of calculations to explore the ionizing interactions of electromagnetic radiation and charged particles with atoms and ions. The collaborators are Steven Manson of Georgia State University and Pranawa Deshmukh of the Indian Institute of Technology, Madras. During the initial phase of the project, the Indian collaborator will be supported with travel and living expenses to do developmental work using the computational facilities at Georgia State University. The proposed research will study i) the influence of relativistic interactions in the photoionization of high-z atoms using the RRPA formalism with enough channels to obviate truncation errors, ii) investigate the inner shell threshold behavior of photoionization cross sections, iii) explore the photoionization of ions with the RRPA technology, iv) examine the systematics of generalized oscillator strengths for neutral atoms, excited states, and atomic ions. Scope: This research will provide training for graduate and advanced undergraduate students in the methods of calculating and understanding atomic and molecular structure and collisions. The techniques and computer codes developed will strengthen the theoretical physics program at the collaborating institutions. The results will provide further insight into the basic nature of these fundamental atomic processes which are important in plasma physics, atmospheric, solar, and astrophysics, radiation physics and therapy, and for studies of possible x-ray and nuclear-pumped laser mechanisms. ***