Role of Double Layers in the Formation of Conditions for a Polarization Phase Transition to the Superradiancestate in the Io Flux Tube

Abstract

A possibility of the electron phase transition into cyclotron superradiance mode in a vicinity of the Io flux tube foot in the Jovian magnetosphere has been considered. A high power of cyclotron superradiance allows it to be considered as the main mechanism of decameter Jupiter radiation generation in the form of S-bursts. It was found that the downward electron beams emitted by Io are able to create electric double layers in the form of shock waves. Such waves, when moving along the flux tube, accelerate electrons in the magnetosphere. As a result, the temperature of the electron plasma component decreases considerably. The emerging upward electron beams create conditions favorable for the phase transition into the cyclotron superradiance mode to take place. K e y w o r d s: magnetosphere, superradiance, double layer, plasma.

Vortex structures and electron beam dynamics in magnetized plasma

“…Numerical simulation in [14] showed the possibility of a quasi-stationary DL formation during the interaction of an electron beam with a plasma in the nonrelativistic case. When electron beam with a density of 10 4 cm −3 is injected into the plasma of the Jupiter ionosphere, a DL can form in the region where densities of the beam and plasma are approximately equal.…”

Vortex Structures and Electron Beam Dynamics in Magnetized Plasma

“…In works [10][11][12][13][14], the original model was proposed that describes the generation of a super-powerful Jovian radio emission, which is based on the effect of the Fomin-Dicke collective coherent CSR for a system of inverted electrons at high Landau levels in rarefied magnetized plasma. According to the model, electron beams are accelerated from Io toward Jupiter and are reflected from double electric layers that arise in the plasma of the ionosphere.…”

“…The formation mechanisms of sufficiently strong DLs are also possible, associated with the injection of particles into the plasma, due to the current amplification of the plasma instability. Most of the beam electrons are reflected in the ionosphere by parallel electrical layers Numerical simulations in [14] showed the possibility of a quasi-stationary DL formation during the interaction of an electron beam with a plasma in the nonrelativistic case. When the electron beam with a density of 10 4 cm −3 is injected into the plasma of the Jupiter ionosphere, a DL can be formed in the region, where the densities of the beam and plasma are approximately equal.…”