Transport of thermal plasma above the auroral ionosphere in the presence of electrostatic ion-cyclotron turbulence

V. E. Zakharov (1) , C.-V. Meister (2)

1 KSTU - Kaliningrad State Technical University
2 Astrophysical Institute Potsdam

The electron component of intensive electric currents flowing along the geomagnetic field lines excites turbulence in the thermal magnetospheric plasma. The protons are then scattered by the excited electromagnetic waves, and as a result the plasma is stable. As the electron and ion temperatures of the background plasma are approximately equal each other, here electrostatic ion-cyclotron (EIC) turbulence is considered. In the nonisothermal plasma the ion-acoustic turbulence may occur additionally. The anomalous resistivity of the plasma causes large-scale differences of the electrostatic potential along the magnetic field lines. The presence of these differences provides heating and acceleration of the thermal and energetic auroral plasma. The investigation of the energy and momentum balance of the plasma and waves in the turbulent region is performed numerically, taking the magnetospheric convection and thermal conductivity of the plasma into account. As shown for the quasi-steady state, EIC turbulence may provide differences of the electric potential of ?V?1?10 kV at altitudes of 500 < h < 10 000 km above the Earth's surface. In the turbulent region, the temperatures of the electrons and protons increase only a few times in comparison with the background values.

Domaines: Océan, Atmosphère; Sciences de la Terre

V. E. Zakharov, C.-V. Meister. Transport of thermal plasma above the auroral ionosphere in the presence of electrostatic ion-cyclotron turbulence. Annales Geophysicae, 1999, 17 (1), pp.27-36. ⟨hal-00316490⟩