Found 8 entries in the Bibliography.

Showing entries from 1 through 8


Rapid Enhancements of the Seed Populations in the Heart of the Earth\textquoterights Outer Radiation Belt: A Multicase Study

To better understand rapid enhancements of the seed populations (hundreds of keV electrons) in the heart of the Earth\textquoterights outer radiation belt (L* ~ 3.5\textendash5.0) during different geomagnetic activities, we investigate three enhancement events measured by Van Allen Probes in detail. Observations of the fluxes and the pitch angle distributions of energetic electrons are analyzed to determine rapid enhancements of the seed populations. Our study shows that three specified processes associated with substorm ele ...

Tang, C.; Xie, X.; Ni, B.; Su, Z.; Reeves, G.; Zhang, J.-C.; Baker, D.; Spence, H.; Funsten, H.; Blake, J.; Wygant, J.; . Y. Dai, G;

YEAR: 2018     DOI: 10.1029/2017JA025142

enhanced convection; Substorm Injections; the outer radiation belt; the seed population; ULF waves; Van Allen Probes


Radiation belt seed population and its association with the relativistic electron dynamics: A statistical study

Using the particle data measured by Van Allen Probe A from October 2012 to March 2016, we investigate in detail the radiation belt seed population and its association with the relativistic electron dynamics during 74 geomagnetic storms. The period of the storm recovery phase was limited to 72 h. The statistical study shows that geomagnetic storms and substorms play important roles in the radiation belt seed population (336 keV electrons) dynamics. Based on the flux changes of 1 MeV electrons before and after the storm peak, ...

Tang, C.; Wang, Y.; Ni, B.; Zhang, J.-C.; Reeves, G.; Su, Z.; Baker, D.; Spence, H.; Funsten, H.; Blake, J.;

YEAR: 2017     DOI: 10.1002/2017JA023905

relativistic electrons; Substorm Injections; the outer radiation belt; the seed population; Van Allen Probes


The role of ring current particle injections: Global simulations and Van Allen Probes observations during 17 March 2013 storm

We simulate substorm injections observed by the Van Allen Probes during the 17 March 2013 storm using a self-consistent coupling between the ring current model RAM-SCB and the global MHD model BATS-R-US. This is a significant advancement compared to previous studies that used artificially imposed electromagnetic field pulses to mimic substorm dipolarization and associated inductive electric field. Several substorm dipolarizations and injections are reproduced in the MHD model, in agreement with the timing of shape changes in ...

Yu, Yiqun; Jordanova, Vania; Welling, Dan; Larsen, Brian; Claudepierre, Seth; Kletzing, Craig;

YEAR: 2014     DOI: 10.1002/2014GL059322

ring current dynamics; self-consistent treatment of fields and plasma; Substorm Injections; Van Allen Probes


Chorus wave generation near the dawnside magnetopause due to drift shell splitting of substorm-injected electrons

We study the relationship between the electron injection and the chorus waves during a substorm event on 23 March 2007. The chorus waves were detected at high geomagnetic latitude (\~70\textdegreeS) Antarctic observatories in the range of 0600\textendash0900 h in magnetic local time (MLT). Electrons drifting from the injection event were measured by two LANL spacecraft at 0300 and 0900 MLT. The mapping of auroral brightening areas to the magnetic equator shows that the injection occurred in an MLT range of 2200\textendash240 ...

Min, Kyungguk; Lee, Jeongwoo; Keika, Kunihiro;

YEAR: 2010     DOI: 10.1029/2010JA015474

chorus and substorm; electron drift; RBSP; Substorm Injections; Van Allen Probes


Substorm injections produce sufficient electron energization to account for MeV flux enhancements following some storms

One of the main questions concerning radiation belt research is the origin of very high energy (>1 MeV) electrons following many space storms. Under the hypothesis that the plasma sheet electron population is the source of these electrons, which are convected to the outer radiation belt region during substorms, we estimate the flux of particles generated at geosynchronous orbit. We use the test particle method of following guiding center electrons as they drift in the electromagnetic fields during substorm dipolarization. Th ...

Mithaiwala, M.; Horton, W.;

YEAR: 2005     DOI: 10.1029/2004JA010511

Substorm Injections


Substorm injection of relativistic electrons to geosynchronous orbit during the great magnetic storm of March 24, 1991

The great March 1991 magnetic storm and the immediately preceding solar energetic particle event (SEP) were among the largest observed during the past solar cycle, and have been the object of intense study. We investigate here, using data from eight satellites, the very large delayed buildup of relativistic electron flux in the outer zone during a 1.5-day period beginning 2 days after onset of the main phase of this storm. A notable feature of the March storm is the intense substorm activity throughout the period of the rela ...

Ingraham, J.; Cayton, T.; Belian, R.; Christensen, R.; Friedel, R.; Meier, M.; Reeves, G.; Takahashi, K;

YEAR: 2001     DOI: 10.1029/2000JA000458

Substorm Injections


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


Substorm electron injections: Geosynchronous observations and test particle simulations

We investigate electron acceleration and the flux increases associated with energetic electron injections on the basis of geosynchronous observations and test-electron orbits in the dynamic fields of a three-dimensional MHD simulation of neutral line formation and dipolarization in the magnetotail. This complements an earlier investigation of test protons [Birn et al., 1997b]. In the present paper we consider equatorial orbits only, using the gyrocenter drift approximation. It turns out that this approximation is valid for e ...

Birn, J.; Thomsen, M.; Borovsky, J.; Reeves, G.; McComas, D.; Belian, R.; Hesse, M.;

YEAR: 1998     DOI: 10.1029/97JA02635

Substorm Injections