Crossing a narrow-in-altitude turbulent auroral acceleration region

Ponderomotive Acceleration in the Auroral Region A Kinetic Simulation

Alfvtn waves with frequencies of the order of several Hertz have been observed in the auroral region. These waves are thought to be responsible for the acceleration f !0nosphen'c particles out of the ionosphere and into the magnetosphere. As an Alfvtn wave propagates into an inhomogeneous ionosphere, the amplitude of the wave decreases resulting in a gradient in the electric field and a pondero...

Particle Acceleration and Wave Phenomena in the Auroral Region

1 I n t r o d u c t i o n The auroral region of the terrestrial magnetosphere is a fascinating part of space, and also a part that can be investigated in some detail with satellites, sounding rockets and groundbased instruments. The second EGS Alfv~n conference held in Stockholm May 3-7 1999 was devoted to auroral particle acceleration and related topics. This meeting produced a variety of inte...

Auroral ion outflow: low altitude energization

The SIERRA nightside auroral sounding rocket made observations of the origins of ion upflow, at topside F-region altitudes (below 700 km), comparatively large topside plasma densities (above 20 000/cc), and low energies (10 eV). Upflowing ions with bulk velocities up to 2 km/s are seen in conjunction with the poleward edge of a nightside substorm arc. The upflow is limited within the poleward e...

Section III Auroral Region

Superthermal Ion Signatures of Auroral Acceleration Processes

The retarding ion mass spectrometer on the Dynamics Explorer 1 spacecraft has generated a unique data set which documents, among other things, the occurrence of non-Maxwellian superthermal features in the auroral topside ionosphere distribution functions. In this paper, we provide a representative sampling of the observed features and their spatial morphology as observed at altitudes in the ran...