1. Space Vehicles Directorate; Air Force Research Laboratory, Kirtland Air Force Base; Albuquerque New Mexico USA
2. Institute for Scientific Research; Boston College; Chestnut Hill Massachusetts USA
3. Now at Space Dynamics Laboratory; Logan Utah USA
4. QinetiQ; Malvern United Kingdom
5. Now at University of Birmingham; Birmingham United Kingdom
6. Plasma Physics Division; Naval Research Laboratory; Washington District of Columbia USA
7. Department of Electrical and Computer Engineering; University of Illinois at Urbana-Champaign; Urbana Illinois USA