HR: 0830h
AN: SH31A-1091    [PDF]
TI: Production of Energetic Electrons during Magnetic Reconnection
AU: * Drake, J F
EM: drake@plasma.umd.edu
AF: University of Maryland, IREAP, College Park, MD 20742 United States
AU: Swisdak, M
EM: swisdak@glue.umd.edu
AF: University of Maryland, IREAP, College Park, MD 20742 United States
AU: Shay, M A
EM: shay@glue.umd.edu
AF: University of Maryland, IREAP, College Park, MD 20742 United States
AB: A new mechanism for the production of energetic electrons during magnetic reconnection is being explored to understand spacecraft observations in the Earth's magnetosphere and in astrophysical systems. Energetic electrons with $100's$ of kev have long been observed in the Earth's magnetotail ({\it e.g.} Baker and Stone 1977) and their presence has been linked to magnetic reconnection. More recent data suggests that the source of these particles is the dissipation region (Oieroset, {\it et al.}, 2002), which significantly constrains possible acceleration mechanisms. Single x-line encounters can not produce these energetic particles. We suggest that electrons can have multiple interactions with the dissipation region by scattering off of turbulence which develops in the outflow region and then migrating upstream along magnetic field lines adjacent to the separatrix. Particle simulations reveal that this turbulence is driven by the electron pressure anisotropy ($T_\perp \gg T_\parallel$ with $kc/\omega_{pe}\sim 1$ and $\gamma\sim\Omega_{ce}$) (Vedenov, et al 1961). Large $T_\perp$ results from electron compression during merger with the ion outflow downstream from the x-line. Analytic arguments suggest that the resulting energy spectra should take the form of a power law with spectral index $k=\ln(m_i/m_e)/2\ln 2=5.4$, which is in the range of observations. The calculations extend the work of Hoshino, {\it et al.,} 2001.
DE: 7835 Magnetic reconnection
DE: 7843 Numerical simulation studies
DE: 7863 Turbulence
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting