ISEE/IMP Observations of simultaneous upstream ion events

Journal Article · Fri Jul 01 04:00:00 EDT 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA07p05635· OSTI ID:5811465

Mitchel, D G; Roelof, E C; Sanderson, T R; Reinhard, R; Wenzel, K

Propagation of upstream energetic (50--200 keV) ions is analyzed in sixteen events observed simulataneously by solid state detectors on ISEE 3 at approx.200 R/sub E/ and on IMP 8 at approx.35 R/sub E/ from the earth. Conclusions are based on comparisons of the pitch angle distributions observed at the two spacecraft and transformed into the solar wind frame. They are beamlike at ISEE 3 and are confined to the outward hemisphere. When IMP 8 is furtherest from the bow shock, they are also usually beamlike, or hemispheric. However, when IMP 8 is closer to the bow shock, pancakelike distributions are observed. This systematic variation in the IMP 8 pitch angle distributions delimits a scattering region l< or approx. =14 R/sub E/ upstream of the earth's bow shock (l measured along the interplanetary magnetic field) that dominates ion propagation, influences the global distribution of fluxes in the foreshock, and may play a role in acceleration of the ions. When IMP 8 is beyond lapprox.15 R/sub E/, the propagation appears to be essentially scatter-free between IMP 8 and ISEE 3; this is deduced from the absence of earthward fluxes at IMP 8 as well as the tendency for the spin-averaged fluxes to be comparable at the two spacecraft.

• Research Organization: Applied Physics Laboratory, The Johns Hopkins University, Laurel, Maryland 20707
• OSTI ID: 5811465
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88: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
BEAMS
EARTH ATMOSPHERE
ENERGY RANGE
IMP SATELLITES
INCLINATION
INTERPLANETARY MAGNETIC FIELDS
ION BEAMS
KEV RANGE
MAGNETIC FIELDS
MAGNETOSPHERE
RADIATION STREAMING
SATELLITES
SCATTERING
SOLAR ACTIVITY
SOLAR WIND