Mass and electron densities in the inner magnetosphere during a prolonged disturbed interval
Article first published online: 24 JAN 2007
Copyright 2007 by the American Geophysical Union.
Geophysical Research Letters
Volume 34, Issue 2, January 2007
How to Cite
2007), Mass and electron densities in the inner magnetosphere during a prolonged disturbed interval, Geophys. Res. Lett., 34, L02108, doi:10.1029/2006GL028254., , , and (
- Issue published online: 24 JAN 2007
- Article first published online: 24 JAN 2007
- Manuscript Accepted: 13 DEC 2006
- Manuscript Revised: 6 DEC 2006
- Manuscript Received: 22 SEP 2006
 The equatorial plasma density and composition at L = 2.5 were studied during an extended disturbed interval using field line resonance measurements (yielding plasma mass density), naturally and artificially stimulated VLF whistlers (electron number density) and IMAGE EUV observations (plasmapause position and line-of-sight He+ intensity). During the storm the plasmapause moved to L < 2.5 and at least one density notch and drainage plume formed. These features were evident in all the data sets for some days. One notch extended from 2.4–4.5 RE and spanned <4 hours in MLT. Plume mass and electron densities were enhanced by a factor of about 3. In the plasmasphere and plasmatrough the H+: He+: O+ composition by number was ∼82:15:3. However, just outside the plasmapause the O+ concentration exceeded 50%, suggesting the presence of an oxygen torus.