1. Center for Space Physics; Boston University; Boston; Massachusetts; USA
2. Department of Physics; University of New Hampshire; Durham; New Hampshire; USA
3. Smithsonian Astrophysical Observatory; Cambridge; Massachusetts; USA
4. The Aerospace Corporation; El Segundo; California; USA
5. The Aerospace Corporation; Chantilly; Virginia; USA
6. Department of Nuclear Engineering; University of Tennessee; Knoxville; Tennessee; USA
7. Southwest Research Institute; Boulder; Colorado; USA