Suprathermal particle precipitation and small-scale auroral features
Abstract
Suprathermal particles precipitating in the nightside auroral region excite several phenomena. Among these are optical emissions at multiple wavelengths of and pouring energy into the tail of the Maxwellian energy distribution that enhance 'plasma lines' in the incoherent scatter spectrum. Plasma lines are scatter from the Langmuir waves that get enhanced above detectability threshold in the presence of energetic particles and are typically used to get the most precise ground-based measurement of ionospheric electron densities by ISRs. The Sondrestrom radar in Greenland is particularly sensitive to the energy input that enhance plasma lines for the Langmuir wave frequency in the range of 7-10 MHz [Nilsson et al, 1996]. High temporal cadence observations made using this capability on the ISR and narrow and wide field-of-view imagers co-located at the Sondrestrom site show enhanced particle fluxes during transient and patchy small-scale structuring in aurora. We will show these observations along with impact on phase scintillations observed using a co-located GNSS receiver. The observations will be accompanied by model simulation for particle energies and fluxes as well as discussion on magnetospheric sources giving rise to the observed phenomena.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFMSA42B..09B
- Keywords:
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- 2427 Ionosphere/atmosphere interactions;
- IONOSPHERE;
- 2431 Ionosphere/magnetosphere interactions;
- IONOSPHERE;
- 2455 Particle precipitation;
- IONOSPHERE;
- 7807 Charged particle motion and acceleration;
- SPACE PLASMA PHYSICS