Plasma waves in the range of the lower hybrid frequency: ISEE 1 and 2 Observations at the Earth's bow shock

Journal Article · Thu Sep 01 04:00:00 EDT 1988 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA093iA09p09695· OSTI ID:6765593

Mellott, M M; Greenstadt, E W

This report presents a characterization of plasma wave noise in the range of the lower hybrid frequency associated with 65 crossings of Earth's bow shock observed by the ISEE 1 and 2 satellites. Wave growth generally becomes detectable at the upstream edge of the shock foot, increases at the upstream edge of the shock ramp, peaks within the ramp, and then quickly decays to steady downstream values. The upstream extent of the noise is on the same order as that of specularly reflected gyrating ions. Similar profiles were observed in subcritical and supercritical shocks, and no special behavior was associated with the first critical Mach number. Spectra in the foot and ramp were similar in shape, although the noise was 1 to 2 orders of magnitude more intense in the shock ramps than in the feet. Low frequency electric field spectra are rather flat, with spectral indices approx.-2 to -1. Magnetic spectra are steeper, with spectral indices approx.-4. Electric field intensities are positively correlated with solar wind speed and inversely related to electron beta and Mach number. Magnetic components are positively correlated with Mach number and beta. These results are generally consistent with suggestions that the noise consists of lower hybrid waves driven by reflected gyrating ions in the foot, and by additional instabilities, such as the cross-field current, in the shock ramp. copyright American Geophysical Union 1988

• Research Organization: Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa
• OSTI ID: 6765593
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 93:A9; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRIC FIELDS
EXPLORER SATELLITES
HEATING
MACH NUMBER
NOISE
PLASMA HEATING
PLASMA WAVES
SATELLITES
SHOCK WAVES
SOLAR ACTIVITY
SOLAR WIND
VELOCITY