The emission of waves via Cherenkov effect is studied for a satellite orbiting the ionosphere and interacting actively with the surrounding plasma via a dipole magnetic field. The orbit height is chosen to be in the range 500-2000 km, in order to maximize the collective response of the plasma. The dispersion relation, in the cold plasma approximation, shows that the excitation occurs mainly for electron-cyclotron waves, namely whistler waves with frequencies in the proximity of the electron cyclotron resonance and the lower-hybrid frequency. The phase velocity is calculated as a function of the angles with respect of the satellite motion and of the Earth magnetic field, and the Mach cone is drawn for each emission frequency. The differential power emitted is calculated for this frequency range in the linear regime. As a result, the radiation power for a magnetized satellite is obtained.
Cherenkov emission of electron-cyclotron waves by a magnetized satellite orbiting the ionosphere
PEGORARO, FRANCESCO
2010-01-01
Abstract
The emission of waves via Cherenkov effect is studied for a satellite orbiting the ionosphere and interacting actively with the surrounding plasma via a dipole magnetic field. The orbit height is chosen to be in the range 500-2000 km, in order to maximize the collective response of the plasma. The dispersion relation, in the cold plasma approximation, shows that the excitation occurs mainly for electron-cyclotron waves, namely whistler waves with frequencies in the proximity of the electron cyclotron resonance and the lower-hybrid frequency. The phase velocity is calculated as a function of the angles with respect of the satellite motion and of the Earth magnetic field, and the Mach cone is drawn for each emission frequency. The differential power emitted is calculated for this frequency range in the linear regime. As a result, the radiation power for a magnetized satellite is obtained.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
