Mass loading in the CRIT II CIV experiment

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:153873

Brenning, N; Bolin, O ^[1]

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1. Royal Inst. of Technology, Stockholm (Sweden)

The CRIT II rocket was launched in 1989 from Wallops Island with the objective of studying the critical ionization velocity (CIV) phenomenon. The experiment consisted of two payloads located on close to the same magnetic field line. At an altitude of approximately 400 km two shaped charge explosions of neutral barium, aimed directly at the main payload, took place. Full three dimensional vector measurements were made, at both the main and the sub payload, of the electric and magnetic fields resulting from the interaction of these neutral barium beams with the ambient ionosphere. The analysis of the electric and magnetic data shows rather clearly that one may consider the low frequency features, below the ambient oxygen gyro frequency, in the CRIT II experiment as being well understood. The analysis also resolves the competition between the homogeneous and the inhomogeneous model for CIV, and a combined model is emerging with components of both. A gradual transition from one to the other, depending on the ionization rate as originally proposed by Haerendel, agrees with CRIT II observations, and gives a natural coupling between the energy and momentum transfer mechanisms. The only assumptions are (1) that instability-associated Hall currents flow along the wave fronts, and (2) these high frequency Hall currents merge into field-aligned mass loading currents in a macroscopic low frequency current system. The authors propose a matching region, where this merging takes place, to exist between the beam and the distant ionosphere.

• OSTI ID: 153873
• Report Number(s): CONF-950612--; ISBN 0-7803-2669-5
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BEAM-PLASMA SYSTEMS
DATA ANALYSIS
ELECTRIC CURRENTS
IONIZATION
IONOSPHERE
MATHEMATICAL MODELS
NEUTRAL ATOM BEAM INJECTION
RESEARCH PROGRAMS