The radiation belt “source” (a few to tens of keV), “seed” (hundreds and “relativistic” (>1 MeV) electrons are highly fabricated by geomagnetic storms or substorms. present study statistically analyzed the phase-space density (PSD) at first adiabatic invariant μ = 101–104 MeV/G between L* (the inversion third invariant) from 2.5 5.5 in response storms. statistical results indicate that after storms, more than 25% relativistic electron PSD were pumped > ∼3.5, with a peak...

Relativistic electrons (>1 MeV) confined within the Earth's radiation belt, which presents significant hazards to astronauts and spacecraft, potentially arise from sub-relativistic (a few hundred keV) through radial diffusion wave–particle interactions. This study a novel artificial neural network (ANN) prediction model for belt relativistic electron flux at typical energy of 1.8 MeV, utilizing concurrent measurements fluxes Ek = 78–871 keV Van Allen Probe observations between 2012...

The energy spectra of the Earth's radiation belt electrons provide easy access to analyze dynamics inner magnetosphere. present study quantitatively investigates spectral distributions electron phase space density (PSD) at μ = 10–104 MeV/G (μ is first adiabatic invariant) within L* 2.5–6.0 (L* denotes third under TS04 geomagnetic coordinate, based on Van Allen Probe observations from 2012 2019. Statistical results reveal that most observed PSD can also be classified into three types,...

The bump-on-tail electron flux energy spectral distributions in the Earth's radiation belt are widely observed and have been proven to be generated by plasmaspheric hiss-led wave–particle interactions. Here, we report discuss prompt disappearance of them induced high solar wind dynamic pressure (Pdyn) combined with substorms on 12–13 March 2014. To remove potential adiabatic influence, fluxes all converted phase space density TS04 geomagnetic coordinate. Immediately after Pdyn reached its...

Relativistic electrons (>1 MeV) saturating Earth's outer radiation belt is widely regarded as a vital risk to human astronomical activities. In the present work, we construct an artificial neural network model predict relativistic electron phase space density (PSD) at μ = 1000 MeV/G (the first adiabatic invariant) with K 0.08 G1/2RE and 0.17 second L* third ranging from 2.0 5.5, based on Van Allen Probe-A observations 2012 2019. The historical values of solar wind, geomagnetic...

Geomagnetic indices including AE (Auroral Electrojet), AU (Upper envelopes of AE), AL (Lower and Dst (Disturbance Storm Time) are widely considered signatures geomagnetic storms or substorms that triggered by solar wind plasma fluids magnetic fields impinging the Earth's magnetosphere. They crucial for comprehending predicting particle dynamics within near-Earth space. In present study, a forecast model utilizing Long Short-Term Memory (LSTM) Neural Network was constructed training more than...

The energetic protons trapped within the Earth's radiation belt play a crucial role in substantially impacting behavior of ring current, which turn affects dynamics particles. Here, we statistically analyze and discuss global distributions temporal evolutions them at energies from 55 keV to 489 by using 7-year (2012–2019) observations storm probes ion composition experiment onboard Van Allen Probes. show that low-energy (55–148 keV) are distributed higher L shells (L > 4), can deeply...

Energetic protons trapped in the radiation belt, as a vital component of ring current system, are observationally and theoretically modulated by geomagnetic disturbances. Utilizing Van Allen Probe observations, we statistically analyzed their temporal variations at 55–489 keV well pitch angle distributions (PADs) index n (fitted sinn∂, where ∂ is angle) response to storms. It shows that low energies more easily accelerated during The threshold accelerations becomes greater for high-energy...

The temporal and spatial evolution of the energetic protons in Earth's radiation belt is highly correlated with substorm activities. Understanding variations pitch angle distributions (PADs) would be an important convenient approach to better distinguish dominant mechanisms. Based on Van Allen Probe observations from 2012 2019, present study surveyed by fitting them as a function sin n∂ (where ∂ n fitted power-low index). global show that “typical” (n > 2) pancake PADs occur more...

We report a specular loss event of radiation belt electrons induced by moderate geomagnetic storm on April 4, 2017, using Van Allen Probe observations. During the initial phase, when solar wind dynamic pressure (Pdyn) reached 12 nPa, at Ek > ∼200 keV experienced partial loss, followed noticeable energy dispersion, which pronouncedly occurred larger pitch angles higher L shells. main both probes witnessed significant electron flux depletion all energies from 54 to 2.6 MeV dusk-night...

High-energy particles in geosynchronous orbit (GEO) present significant hazards to astronauts and artificial satellites, particularly during extreme geomagnetic activity conditions. In the study, based on observations onboard GOES-15 (Geostationary Operational Environmental Satellites) spanning from 2011 2019 as well historical values of solar wind indices, an neural network model was established predict temporal evolution GEO sub-relativistic relativistic (>0.8 MeV >2 MeV)...