Can we estimate wave heating with fully kinetic 3-D simulations of the Farley-Buneman Instability?
Abstract
The Farley-Buneman (FB) instability is a collisional two-stream plasma instability observed in the electrojet of the E region ionosphere. This instability develops when the polarization electric field across this region causes electrons to E⃗ × B⃗ drift substantially faster than the sound speed. This instability causes much of the common E-region radar reflections, allowing probing of this region. In the auroral electrojet, it also modifies electrojet conductivity by heating and transporting electrons across the geomagnetic field [Foster, Geophys. Res. Lett, 2000 and Oppenheim, Ann. Geophys., 1997]. In this paper, we will present the first fully 3-D kinetic simulations of a saturated FB and use them to explore the physics of electron heating and transport. In the last the last decade numerical simulations have become an important tool in exploring the nonlinear behavior of this instability. However, these simulations have been limited to 2-D and generally have represented electron dynamics with a fluid model while resolving ions kinetically with a particle-in-cell method (PIC) [see Oppenheim, et. al., Geophys. Res. Lett., 1996] or they have failed to reach saturation [Janhunen, J. Geophys. Res., 1994]. Taking advantage of a new generation of massively parallel, supercomputers, we can represent electron dynamics using a fully kinetic PIC algorithm. This allows us to simulate electron temperature variations as well as kinetic effects instead of making a simplifying set of assumptions about electron evolution. We will compare the simulated evolution of the 3-D FB instability with those calculated by 2-D kinetic and hybrid simulations. Further, we will evaluate electron heating effects and the implications for the ionosphere.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2006
- Bibcode:
- 2006AGUSMSA44A..06O
- Keywords:
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- 2407 Auroral ionosphere (2704);
- 2431 Ionosphere/magnetosphere interactions (2736);
- 2437 Ionospheric dynamics;
- 2439 Ionospheric irregularities;
- 2471 Plasma waves and instabilities (2772)