Generation of broadband noise in the magnetotail

Technical Report · Sun Mar 01 04:00:00 EST 1987

OSTI ID:6464615

Dusenbery, P B; Lyons, L R

Generation of electrostatic noise in the geomagnetic tail by ion beams was evaluated. A stationary plasma-sheet electron distribution and streaming ion distributions were assumed. Both warm-ion streams, as observed within the plasma-sheet boundary layer, and cold-ion streams, as expected from upward-flowing ionospheric ions, are considered. Warm-ion streams by themselves are found to be stable, whereas a cold-ion stream by itself is unstable to the beam-acoustic model. However, wave growth is increased if both cold and warm streams are simultaneously present. These results suggest that the interaction between the warm- and cold-ion streams is responsible for the peak in electrostatic-wave intensities observed within the plasma-sheet boundary layer. For cold and warm ions streaming in the same direction, wave growth peaks for wave normal angles theta = O/sup 0/ and wave frequencies about 0.1 x the electron plasma frequency were found. However, for anti-parallel streaming cold and warm ions, wave growth peaks near theta approx. = 90/sup 0/ and wave frequencies are an order of magnitude smaller. Including counter-streaming warm ions in addition to a cold-ion stream results in wave growth that is a superposition of that for the above two cases.

• Research Organization: Aerospace Corp., El Segundo, CA (USA). Laboratory Operations
• OSTI ID: 6464615
• Report Number(s): AD-A-179136/7/XAB; TR-0086(6940-06)-12
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BACKGROUND NOISE
BEAMS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRONS
ELECTROSTATICS
ELEMENTARY PARTICLES
FERMIONS
ION BEAMS
ION DRIFT
LEPTONS
LOW TEMPERATURE
MAGNETOTAIL
NOISE
PLASMA SHEET
SHEETS
STREAMS
SURFACE WATERS