1. Solar-Terrestrial Environment Laboratory; Nagoya University; Nagoya Japan
2. Physics Department; Lancaster University; Lancaster UK
3. Department of Physics and Astronomy; University College London; London UK
4. Department of Physics; La Trobe University; Melbourne, Victoria Australia
5. National Institute of Polar Research; Tokyo Japan
6. Space Science and Technology Department; Rutherford Appleton Laboratory; Didcot UK
7. University Centre in Svalbard; Longyearbyen Norway