HR: 0830h
AN: SH31A-1085    [PDF]
TI: Anomalous resistivity in non-Maxwellian plasmas
AU: * Petkaki, P
EM: ppe@bas.ac.uk
AF: British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET United Kingdom
AU: Watt, C E
EM: cwatt@Space.UAlberta.CA
AF: University of Alberta, Department of Physics, Edmonton, T6G 2J1 Canada
AU: Horne, R B
EM: rh@bas.ac.uk
AF: British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET United Kingdom
AU: Freeman, M P
EM: mpf@bas.ac.uk
AF: British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET United Kingdom
AB: Vlasov simulations of the current-driven ion-acoustic instability produced in Maxwellian and non-Maxwellian (Lorentzian, $\kappa=2$) electron-ion plasma with number density $7\times 10^6$ $cm^{-3}$, reduced mass ratio $m_i/m_e=25$ and electron to ion temperature ratio $T_e/T_i=1$ are presented and compared. A concise stability analysis of current-driven ion-acoustic waves in Maxwellian and non-Maxwellian plasmas modeled by generalized Lorentzian distribution function with index $2 \le \kappa \le 7$ and electron to ion temperature ratio, $1 \le T_e/T_i \le 100$ is also presented. The ion-acoustic instability is excited in low temperature ratio Lorentzian ($\kappa=2$) plasma for lower absolute electron drift velocity (up to half the critical electron drift velocity of a Maxwellian). The anomalous resistivity resulting from ion acoustic waves in a Lorentzian plasma is a strong function of the electron drift velocity, and in the work presented here varies by a factor of $\sim 100$ for a 1.5 increase in the electron drift velocity. Furthermore, ion-acoustic anomalous resistivity is excited for electron drift velocities that would be stable for Maxwellian plasmas. The magnitude of resistivity which can be generated by unstable ion-acoustic waves maybe important for magnetic reconnection at the magnetopause.
DE: 7827 Kinetic and MHD theory
DE: 7835 Magnetic reconnection
DE: 7867 Wave/particle interactions
DE: 7871 Waves and instabilities
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting