Ionospheric Conductance for Sub-Auroral Latitudes at Equinox Twilight. (2002)
In this note, ionospheric conductivities for electric currents perpendicular to the geomagnetic field are presented. The conductivities have been computed for sub-auroral latitudes for spring and...
Auroral Birkeland Currents and Anomalous Resistance. (2002)
Presented are results from an auroral arc model which illustrate the physical relationship between the auroral Birkeland currents and an assumed anomalous resistance along the geomagnetic field. It...
Strickland,D. J., Book,D. L., Coffey,T. P., Fedder,J. A.
Auroral electron scattering and energy loss are calculated using for the first time a multi-angle equation of transfer at all energies. The results are compared with those obtained using a...
Zalesak,S. T., Fedder,J. A., Ossakow,S. L.
Presented is a possible mechanism for the freezing, or apparent freezing of barium cloud striations and for the formation of long thin sheets of barium on the leading edge of the cloud. The essence...
Zalesak,S. T., Chaturvedi,P. K., Ossakow,S. L., Fedder,J. A.
We show that under realistic ionospheric conditions, barium ion clouds hundreds of meters in diameter can be long-lived, quasi-stable, nonbifurcating structures. These structures may resemble...
Region 1 Birkeland Currents from a Global MHD Simulation of the Magnetosphere. (2002)
The study of large scale geomagnetic field aligned currents, which couple the dynamics of the magnetosphere and the high latitude ionosphere, has been an area of intense research interest in recent...
Cheyenne Mountain Late Time Simulation Results. (2002)
Hain,K., Hain,G., Fedder,J. A.
In this report we present results for the late time evolution of the Cheyenne Mountain nuclear explosion scenario. Results are presented from both the DEMAG simulation code and the MELT simulation...
Mitchell,H. G. , Jr., Fedder,J. A., Keskinen,M. J., Zalesak,S. T.
A magnetic-field-line-integrated model of plasma interchange instabilities is developed for the high latitude ionosphere including magnetospheric coupling effects. We show that primary...
Transverse Motion of High Speed Barium Clouds in the Ionosphere. (2002)
Mitchell,H. G., Fedder,J. A., Huba,J. D., Zalesak,S. T.
Simulation results, based on a field-line-integrated, 2D, electrostatic model, are presented for the motion of a barium cloud injected transverse to the geomagnetic field in the ionosphere at high...
Fast Collisionless Tearing in an Anisotropic Neutral Sheet. (1998)
Chen,J., Palmadesso,P. J., Fedder,J. A., Lyon,J. G.
This document studies the collisionless tearing mode in a neutral sheet in the presence of ion temperature anisotorpy using Vlasov description for both ions and electrons.
MHD (Magnetohydrodynamic) Simulation of a Comet Magnetosphere. (1998)
Fedder,J. A., Brecht,S. H., Lyon,J. G.
This paper presents results of a numerical magnetohydrodynamic simulation of the interaction of the solar wind with a comet. It states that for a steady solar wind and interplanetary magnetic field...
The Solar Wind-Magnetosphere-Ionosphere Current-Voltage Relationship. (1998)
The nature of the solar wind-magnetosphere-ionosphere (SW-M-I) coupling has been a subject of intense study and scientific interest. We report results from a numerical simulation of the SW-M-I system...
Nonlinear Evolution of the Kelvin-Helmholtz Instability in the High Latitude Ionosphere. (1998)
Keskinen, M. J., Mitchell, H. G., Fedder, J. A., Satyanarayana, P., Zalesak, S. T.
The nonlinear evolution of the electrostatic Kelvin Helmholtz instability, resulting from velocity-sheared plasma flows perpendicular to an ambient magnetic field, has been studied including Pedersen...
Keskinen, M. J., Fedder, J. A.
The phenomenological models of global electron density for the natural ionosphere of Ching and Chiu (1973) and Chiu (1975) have been extended to both lower (60 km) and higher (36,000 km) altitudes....
Preliminary Study of the Dynamics of High Latitude Nuclear Plumes. (1998)
This memorandum reports the first results of a preliminary study of the late time behavior of a HANE plasma plume at high-latitude and its interaction with the dynamic plasma processes existing...
Effect of Diurnal Convection on Trapped Thermal Plasma in the Outer Plasmasphere. (1997)
Reynolds, M. A., Ganguli, G., Fedder, J. A., Melendez-Alvira, D. J.
A kinetic, multi species model of the plasmasphere is constructed which includes the effect of convection and corotation electric fields on trapped particles in drifting flux tubes. The resulting...
Keskinen, M. J., Huba, J. D., Zalesak, S. T., Fedder, J. A., Mitchell, H. G.
The Naval Research Laboratory high latitude ionosphere-magnetosphere mesoscale coupling model has been generalized to include scale-size dependent magnetospheric coupling and E-region Hall and...