Nonlinear electrostatic waves in the auroral plasma
- 13 May 2020
- journal article
- research article
- Published by IOP Publishing in Physica Scripta
- Vol. 95 (7), 075602
- https://doi.org/10.1088/1402-4896/ab92db
Abstract
Nonlinear electrostatic waves in a two-component magnetized plasma comprising of cold ions and suprathermal electrons following $\kappa$-distribution have been analyzed. The nonlinear electrostatic waves are considered to be propagating at an oblique direction to the ambient magnetic field. A parametric study of the effect of initial driving electric field amplitude (E$_0$), wave Mach number (M), spectral index ($\kappa$), propagation angle ($\alpha$) and ion drift velocity ($\delta$) on the evolution and the existence domain of nonlinear electric field structures is carried out. The theoretical plasma model is able to generate electrostatic ion cyclotron and ion acoustic waves, with the variation in the initial driving electric field amplitude and Mach number. It is observed that with increase in the driving strength the electric field structures evolve from sinusoidal to sawtooth to highly spiky bipolar waveforms. The presence of $\kappa-$ electrons is perceived to reduce the initial driving strength required to generate spiky bipolar electric field structures as compared to Boltzmann-electrons. Further, the period of the waveforms were found to decrease with increase in $\kappa$. The electric field amplitude and the phase speed of the bipolar structures predicted by the theoretical model is found to be in the range of observed electric field and speed in auroral region by the FAST satellite.
Keywords
This publication has 51 references indexed in Scilit:
- THEMIS observations of electrostatic ion cyclotron waves and associated ion heating near the Earth's dayside magnetopauseJournal of Geophysical Research: Space Physics, 2015
- The association of electrostatic ion cyclotron waves, ion and electron beams and field‐aligned currents: FAST observations of an auroral zone crossing near midnightGeophysical Research Letters, 1998
- Linear stability of the H+ ‐ O+ two‐stream interaction in a magnetized plasmaJournal of Geophysical Research, 1988
- Low‐frequency electrostatic noise due to velocity shear instabilities in the regions of magnetospheric flow boundariesJournal of Geophysical Research, 1987
- Ion waves and upgoing ion beams observed by the Viking satelliteGeophysical Research Letters, 1987
- The relationship of field‐aligned currents to electrostatic ion cyclotron wavesJournal of Geophysical Research, 1981
- Electrostatic hydrogen cyclotron waves near one Earth radius altitude in the polar magnetosphereGeophysical Research Letters, 1978
- Observations of Paired Electrostatic Shocks in the Polar MagnetospherePhysical Review Letters, 1977
- Evidence that the electrostatic ion cyclotron instability is saturated by ion heatingPhysics of Fluids, 1975
- Topside current instabilitiesJournal of Geophysical Research, 1971