Perpendicular heating of cold ions and fast magnetosonic waves in the inner magnetosphere observed by Arase (ERG) satellite
Abstract
Fast magnetosonic (MS) waves are commonly observed in the equatorial region of the inner magnetosphere. MS waves can play an important role for both accerlerating and scattering the high-energy electrons. Also, past numerical simulations show MS waves can accelerate cold ions through cyclotron resonance, although the observational evidence is still unclear. Arase (ERG) satellite found events of perpendicular heating of cold ions simultaneously with plasma wave activities of the MS waves. We found more than 200 events of the perpendicular heating of low-energy (10eV/q - a few keV/q) ions in a period between April 2017 to June 2018, and 70% of them coincide with the MS waves. These heated ions are distributed to all the MLT regions within magnetic latitude of +/-10deg, which is consistent with the region where the MS waves frequently observed. Except for the perpendicular heating by the MS waves, there are possible processes which can produce the enhancement of perpendicular ion flux, such as charge exchange and/or Coulomb collision losses at low altitude, and pitch angle dependence of ion drift around the Earth. We will present the observational results of the heated ions in perpendicular direction and the MS waves and possible mechanisms to produce them.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSM41D3276A
- Keywords:
-
- 2730 Magnetosphere: inner;
- MAGNETOSPHERIC PHYSICS;
- 2774 Radiation belts;
- MAGNETOSPHERIC PHYSICS;
- 7807 Charged particle motion and acceleration;
- SPACE PLASMA PHYSICS;
- 7867 Wave/particle interactions;
- SPACE PLASMA PHYSICS