Magnetic field orientation and suprathermal ion streams in the earth's foreshock

Journal Article · Tue Jul 01 04:00:00 EDT 1980 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA085iA07p03473· OSTI ID:5052408

Greenstadt, E W; Russell, C T; Hoppe, M

The different populations of backstreaming ions found earlier with ISEE instruments outside the earth's bow shock were organized by the orientation of the IMF to the shock in the plane containing B/sub SW/ and the solar ecliptic X axis (the B-X plane). The associations of ion classes with field geometry and shock structure are shown by means of computer-drawn three-dimensional sketches. Particles of several keV, or about 10 times the solar wind streaming energy, left the shock as 'reflected' beams in a guiding center direction determined by B/sub SW/ and the interplanetary drift velocity. Their area of departure was the part of the shock where the transition from quasi-perpendicular to quasi-parallel structre began. sightly farther toward the quasi-parallel portion of the shock, particles of lower energy escaped upstream, widening the ion spectra, exciting small magnetic waves, and forming a class of 'intermediate' ions. Finally, in direct connection with he quasi-parallel structure, ions leaving the shock formed the 'diffuse' group, containing a wide distribution of energies including high values well beyond any recorded in the other two classes. Sources of the various groups are postulated.

• Research Organization: Space Sciences Department, TRW Defense and Space Systems Group, Redondo Beach, California 90278
• OSTI ID: 5052408
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 85:A7; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BACKSCATTERING
CHARGED PARTICLES
DIFFUSION
INTERPLANETARY MAGNETIC FIELDS
INTERPLANETARY SPACE
IONS
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
PLASMA DRIFT
SCATTERING
SOLAR ACTIVITY
SOLAR WIND
SPACE