Solar wind electrons: Parametric constraints

Journal Article · Wed Sep 01 04:00:00 EDT 1999 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/1999JA900244· OSTI ID:688001

Gary, S P; Neagu, E; Skoug, R M ^[1]; Goldstein, B E ^[2]

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1. Los Alamos National Laboratory, Los Alamos, New Mexico (United States)
2. Jet Propulsion Laboratory, Pasadena, California (United States)

Solar wind electrons are often observed to consist of two distinguishable components, a thermal, more dense core and a suprathermal, less dense halo. In this core/halo model linear Vlasov theory for the whistler heat flux instability predicts dimensionless heat flux thresholds which decrease as the electron core beta, {tilde {beta}}{sub {parallel}c}, increases. It has been proposed that this theoretical threshold corresponds to an observable upper bound on the electron heat flux. Linear theory also predicts that there is a critical value of {tilde {beta}}{sub {parallel}c} below which the whistler heat flux instability does not have appreciable growth in the solar wind; there is another suggestion that this corresponds to an observable lower bound on {tilde {beta}}{sub {parallel}c}. These two proposals are examined by comparison of linear theory and data from the initial in-ecliptic phase of the Ulysses mission. The instability threshold does provide a statistical constraint on observed solar wind heat fluxes, and the critical {tilde {beta}}{sub {parallel}c} of theory is not inconsistent with a statistical lower bound on the observations of that parameter. {copyright} 1999 American Geophysical Union

• OSTI ID: 688001
• Journal Information: Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: A9 Vol. 104; ISSN 0148-0227; ISSN JGREA2
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ASTROPHYSICS
ELECTRON TEMPERATURE
ELECTRON-ION COLLISIONS
HEAT FLUX
HEAT TRANSFER
INTERPLANETARY SPACE
PLASMA INSTABILITY
SOLAR WATER HEATERS
SOLAR WIND
WHISTLER INSTABILITY
WHISTLERS