Occurrence distribution of preferential heating events in the Aurora

The FAST satellite has detected a class of ion conic events in which He + is more strongly accelerated than H + or O +. The helium ions in these events typically have 3–30 times the energy of simultaneously observed protons, unlike most conics, in which no strong preferential acceleration occurs. Th...

Full description

Saved in:
Bibliographic Details
Published in:Advances in space research 1999, Vol.23 (10), p.1721-1724
Main Authors: Lund, E.J., Möbius, E., Klumpar, D.M., Kistler, L.M., Popecki, M.A., Klecker, B., Ergun, R.E., McFadden, J.P., Carlson, C.W., Strangeway, R.J.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The FAST satellite has detected a class of ion conic events in which He + is more strongly accelerated than H + or O +. The helium ions in these events typically have 3–30 times the energy of simultaneously observed protons, unlike most conics, in which no strong preferential acceleration occurs. These events are well correlated with the occurrence of electromagnetic ion cyclotron (EMIC) waves and are associated with inverted-V electron distributions. The acceleration mechanism is similar to a mechanism which has been proposed for the acceleration and enrichment of 3He in impulsive solar flares. We present a statistical study of such events in the FAST data set. We show that these events are found primarily in the pre-midnight sector and that their occurrence distribution is similar to the distributions previously found for inverted-V electron events and for EMIC waves.
ISSN:0273-1177
1879-1948
DOI:10.1016/S0273-1177(99)00392-0