Affiliation: | Department of Pure and Applied Physics, Queen's University, Belfast BT7 1NN;Department of Applied Mathematics and Theoretical Physics, Queen's University, Belfast BT7 1NN;Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210-1106, USA;Applied Physics Division, Los Alamos National Laboratory, PO Box 1663, Los Alamos, NM 87545, USA;E. O. Hulburt Center for Space Research, Code 7674W, US Naval Research Laboratory, Washington, DC 20375–5000, USA |