MODULATION OF AURORAL ELECTRONS AT LARGE DISTANCES FROM EARTH

The intensities of auroral electrons with energies of 10, 4 and >2 keV have been measured from a rocket launched into a post-breakup aurora from Andøya in Northern Norway. Changes of intensity with periods greater than one second are found to occur earlier at 10 keV than at the other energies; the average delay between 10 and 4 keV electrons is 0.45 ± 0.1 sec and the average delay between 10 and >2 keV electrons is 0.18 ± 0.06 sec. The delays are interpreted as dispersion effects following modulation at or near the geomagnetic equator on the L = 6 magnetic shell. © 1969.