1. Space Science Center and Department of Physics; University of New Hampshire; Durham New Hampshire USA
2. Now at Space Science and Engineering Division; Southwest Research Institute; San Antonio Texas USA
3. Now at Department of Physics and Astronomy; University of Texas at San Antonio; San Antonio Texas USA
4. National Space Science Center; Chinese Academy of Sciences; Beijing China
5. Max-Plank-Institut für Extraterrestrische Physik; Garching Germany
6. Space Sciences Division, SSTD; Rutherford Appleton Laboratory; Didcot United Kingdom
7. Swedish Institute of Space Physics (IRF); Uppsala Sweden
8. Los Alamos National Laboratory; Los Alamos New Mexico USA