Found 5 entries in the Bibliography.

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Characterization and Evolution of Radiation Belt Electron Energy Spectra Based on the Van Allen Probes Measurements

Based on the measurements of ~100-keV to 10-MeV electrons from the Magnetic Electron Ion Spectrometer (MagEIS) and Relativistic Electron and Proton Telescope (REPT) on the Van Allen Probes, the radiation belt electron energy spectra characterization and evolution have been investigated systematically. The results show that the majority of radiation belt electron energy spectra can be represented by one of three types of distributions: exponential, power law, and bump-on-tail (BOT). The exponential spectra are generally domin ...

Zhao, H.; Johnston, W.R.; Baker, D.N.; Li, X.; Ni, B.; Jaynes, A.N.; Kanekal, S.G.; Blake, J.B.; Claudepierre, S.G.; Reeves, G.D.; Boyd, A.J.;

YEAR: 2019     DOI: 10.1029/2019JA026697

Bump-on-tail energy spectrum; Energy spectrum; Exponential energy spectrum; Plasmapause; Power law energy spectrum; radiation belt electrons; Van Allen Probes


Intelligent Sampling of Hazardous Particle Populations in Resource-Constrained Environments

Sampling of anomaly-causing space environment drivers is necessary for both real-time operations and satellite design efforts, and optimizing measurement sampling helps minimize resource demands. Relating these measurements to spacecraft anomalies requires the ability to resolve spatial and temporal variability in the energetic charged particle hazard of interest. Here we describe a method for sampling particle fluxes informed by magnetospheric phenomenology so that, along a given trajectory, the variations from both tempora ...

McCollough, J.; Quinn, J.; Starks, M.; Johnston, W.;

YEAR: 2017     DOI: 10.1002/2017SW001629

data sampling; magnetospheric plasma; measurement; Solar Energetic Protons; trapped electrons; trapped protons; Van Allen Probes


Release of AE9/AP9/SPM Radiation Belt and Space Plasma Model Version 1.20.002

Johnston, Wm.; O\textquoterightBrien, Paul; Ginet, Gregory;

YEAR: 2015     DOI: 10.1002/2015SW001212


AE9, AP9 and SPM: New Models for Specifying the Trapped Energetic Particle and Space Plasma Environment

The radiation belts and plasma in the Earth\textquoterights magnetosphere pose hazards to satellite systems which restrict design and orbit options with a resultant impact on mission performance and cost. For decades the standard space environment specification used for spacecraft design has been provided by the NASA AE8 and AP8 trapped radiation belt models. There are well-known limitations on their performance, however, and the need for a new trapped radiation and plasma model has been recognized by the engineering communi ...

Ginet, G.; textquoterightBrien, T.; Huston, S.; Johnston, W.; Guild, T.; Friedel, R.; Lindstrom, C.; Roth, C.; Whelan, P.; Quinn, R.; Madden, D.; Morley, S.; Su, Yi-Jiun;

YEAR: 2013     DOI: 10.1007/s11214-013-9964-y

RBSP; Van Allen Probes


The temporal evolution of electron distributions and associated wave activity following substorm injections in the inner magnetosphere

The temporal evolution of electron distributions and associated wave activity following substorm injections in the inner magnetosphere are investigated using data from the CRRES satellite. Equatorial electron distributions and concomitant wave spectra outside the plasmapause on the nightside of the Earth are studied as a function of time since injection determined from the auroral-electrojet index (AE). The electron cyclotron harmonic (ECH) wave amplitudes are shown to be very sensitive to small modeling errors in the locati ...

Meredith, Nigel; Horne, Richard; Johnstone, Alan; Anderson, Roger;

YEAR: 2000     DOI: 10.1029/2000JA900010

Substorm Injections