A chorus generation mechanism is discussed, which is based on interrelation of ELF/VLF noise-like and discrete emissions under the cyclotron wave-particle interactions. A natural ELF/VLF noise radiation is excited by the cyclotron instability mechanism in ducts with enhanced cold plasma density or at the plasmapause. This process is accompanied by a step-like deformation of the energetic electr...

An attempt is made to con®rm the generation mechanism of plasmaspheric ELF hiss emissions observed aboard GEOS-1 satellite in the equatorial region both at small and large wave normal angles by calculating their magnetic ®eld intensities in terms of incoherent Cerenkov radiation mechanism and cyclotron resonance instability mechanism, using appropriate and suitable plasma parameters. The ELF in...

Plasma density is an important factor in determining wave-particle interactions the magnetosphere. We develop a machine-learning-based electron (MLED) model inner magnetosphere using data from Van Allen Probes between September 25, 2012 and August 30, 2019. This MLED physics-based nonlinear network that employs fundamental physical principles to describe variations of density. It predicts plasm...

NASA's Van Allen Probes observed significant, long-lived fluxes of inner belt electrons up to ∼1 MeV after geomagnetic storms in March and June 2015. Reanalysis Magnetic Electron Ion Spectrometer (MagEIS) data with improved background correction showed a clearer picture the relativistic electron population that persisted through 2016 into 2017 above Fennell et al. (2015, https://doi.org/10.1002...

The Van Allen Probe A spacecraft observed strong ?0.5-Hz helium (He+) band and weak ?0.8-Hz hydrogen (H+) EMIC waves on April 17, 2018, at L = ?4.5–5.2, in the dawn sector, near magnetic equator, close to plasmapause. We examined low-energy ion fluxes by Helium Oxygen Proton Electron (HOPE) instrument onboard during wave interval found that He+ flux (<10 eV) enhancements occur nearly simultaneo...

The near-relativistic electron population in the outer Van Allen radiation belt is highly dynamic and strongly coupled to geomagnetic activity such as storms substorms, which are driven by interaction of magnetosphere with solar wind. energy, content, spatial extent electrons can vary on timescales hours days, dictated continuously evolving influence acceleration loss processes. While net chang...