Relationship between diffuse auroral and plasma-sheet electron distribution near local midnight

Technical Report · Tue Aug 01 00:00:00 EDT 1989

OSTI ID:6204536

Schumaker, T L; Gussenhoven, M S; Hardy, D A; Carvillano, R L

A study of the relationship between diffuse auroral and plasma sheet electron distributions in the energy range from 50eV to 20keV in the midnight region was conducted using data from the P78-1 and SCATHA satellites. From 1 1/2 years of data, 14 events were found where the polar-orbiting P78-1 satellite and the near-geosynchronous SCATHA satellite were approximately on the same magnetic field line simultaneously, with SCATHA in the plasma sheet and P78-1 in the diffuse auroral region. For all cases the spectra from the two satellites are in good quantitative agreement. For 13 of the 14 events the pitch angle distribution measured at P78-1 was isotropic for angles mapping into the loss cone at the SCATHA orbit. For one event the P78-1 electron flux decreased with pitch angle toward the field line direction. At SCATHA the distributions outside the loss cone were most commonly butterfly or pancake, although distributions peaked toward the field line were sometimes observed at energies below 1 keV. Electron distributions, as measured where there is isotropy within the loss cone but anistropy outside the loss cone, are inconsistent with current theories for the scattering of electrons weakly dependent on magnetic activity. The average lifetimes exceed those for the case of isotropy at all pitch angles by a factor between 2 and 3 for Kp < or = 2 and approximately 1.5 for Kp > 2.

• Research Organization: Air Force Geophysics Lab., Hanscom AFB, MA (USA)
• OSTI ID: 6204536
• Report Number(s): AD-A-226585/8/XAB
• Resource Relation: Other Information: Pub. in Jnl. of Geophysical Research, Vol. 94, No. A8, 10,061-10,078(1 Aug 1989)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAL ZONES
ELECTRON DENSITY
PLASMA SHEET
AURORAE
CONICAL CONFIGURATION
DIFFUSION
ELECTRONS
ISOTROPY
LOSS CONE
MAGNETIC FIELDS
MAPPING
PLASMA
SATELLITES
SCATTERING
SPATIAL DISTRIBUTION
CONFIGURATION
DISTRIBUTION
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELEMENTARY PARTICLES
FERMIONS
LEPTONS
640201* - Atmospheric Physics- Auroral
Ionospheric
&amp; Magetospheric Phenomena