Devin Huyghebaert (UiT The Arctic University of Norway) The Radar Aurora - Investigating Ionospheric E-region Plasma Turbulence with Coherent Scatter Radars
Devin Huyghebaert (UiT The Arctic University of Norway) wird auf unserem IAP-Kolloquium einen Vortrag zum Thema "The Radar Aurora - Investigating Ionospheric E-region Plasma Turbulence with Coherent Scatter Radars" halten.
Zusammenfassung:
The E-region ionosphere, located at altitudes of 90-150 km above the surface of the Earth, is where a large amount of energy is deposited due to solar-terrestrial magnetohydrodynamic interactions. Electrical currents generated from these interactions flow along the geomagnetic field lines and are able to close in the E-region due to the differential motion between the ions and electrons at those altitudes. The differential motion is a result of the ratio of the ion and electron collision rates with the neutral atmospheric constituents to their respective cyclotron frequencies - the ions are significantly influenced by the neutral background atmosphere while the electrons follow the electromagnetic forces. The difference in velocity can cause instabilities in the plasma to form, specifically the modified two-stream, or Farley-Buneman, instability. This instability creates large fluctuations in the plasma density which can be measured using ionospheric coherent scatter radars.
E-region coherent scatter is also referred to as ‘The Radar Aurora’ due to the tendency for the scatter to be measured during periods of auroral optical emissions. Recent studies regarding the radar aurora using two different auroral coded continuous-wave radar systems will be presented - the Spread Spectrum Interferometric Multistatic meteor radar Observing Network (SIMONe) Norway radars, and the Ionospheric Continuous-wave E-region Bistatic Experimental Auroral Radar (ICEBEAR). What can be determined about the E-region ionosphere through the measurement of the radar aurora will be discussed, and we will explore what future studies are planned using the radar instruments.
