Wave excitation downstream of the low-. beta. , quasi-perpendicular bow shock

Journal Article · Tue May 01 04:00:00 EDT 1990 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA095iA05p06331· OSTI ID:5133016

Brinca, A L ^[1]; Sckopke, N; Paschmann, G ^[2]

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1. Inst. Superior Tecnico, Lisbon (Portugal)
2. Max-Planck-Inst. fuer Physik und Astrophysik, Garching (West Germany)

The authors interpret the low-frequency wave observations of the AMPTE/IRM mission in the downstream region of a marginally supercritical, quasi-perpendicular bow shock. A companion paper on ion heating comprehensively describes the corresponding plasma and wave magnetic field measurements. A simple model of the shocked plasma consisting of a background hydrogen magnetoplasma with anisotropic core protons permeated by a hotter dilute beam of anisotropic protons reproduces the basic features of the wave polarization and frequency spectra: wave activity below the proton cyclotron frequency, sometimes displaying a double-humped structure, with unusual (in space plasmas outside the magnetosphere) dominance of (plasma frame) left-hand-polarized modes. The core and beam anisotropies stimulate electromagnetic (left-hand) ion cyclotron waves in distinct spectral regions, whereas the large downstream Alfven speed (with respect to the beam drift speed) precludes an efficient cyclotron resonant generation of the right-hand magnetosonic modes.

• OSTI ID: 5133016
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 95:A5; ISSN JGREA; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
BARYONS
CYCLOTRON FREQUENCY
CYCLOTRON INSTABILITY
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELEMENTARY PARTICLES
FERMIONS
HADRONS
INSTABILITY
INTERACTIONS
ION WAVES
MAGNETOSHEATH
MATHEMATICAL MODELS
NUCLEONS
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
PLASMA WAVES
POLARIZATION
PROTONS
SATELLITES
SHOCK WAVES
SOLAR ACTIVITY
SOLAR WIND