Seminars

Lecturer: M. Yamauchi (IRF)
Date: 2013-10-17 10:30
Place: Aniara

Morphology of inner magnetospheric low-energy ions

M. Yamauchi
Swedish Institute of Space Physics


Abstract
The inner magnetosphere is the region that geomagnetic field is strong enough to trap ions that gyrates around the magnetic field. These ions are not simply trapped and they drift mainly in the perpendicular direction to the local magnetic field due to non-uniform curved magnetic field and the electric field. Because the electric field plays important roles only for low energy (sub-keV range), such motion makes the low-energy ion distribution a complicated zoo of different types of ions population with different sources. Therefore, no systematic study of low-energy ion population with different source in the inner magnetosphere has been performed yet.

The ion data from 6-year Cluster observation are statistically examined the local time distribution of concentrated ion signatures at 0.1 to few keV range as well as 1-2 hour scale temporal variation of the ion signatures in intensities and energy-latitude dispersion directions. Four commonly-found concentrated ion signatures at 0.1 to few keV range in the inner magnetosphere are examined:

(1) Energy-latitude dispersed structured ions at less than a few keV,
(2) Short-lived dispersionless ion stripes at wide energy ranges extending 0.1~10 keV,
(3) Short-lived low-energy ion bursts at less than few hundred eV.
(4) Equatorially confined low energy structureless warm ions at few tens to few hundred eV.

Created 2013-10-09 15:32:37 by Mats Holmström
Last changed 2013-10-09 15:32:37 by Mats Holmström