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Van Allen Probes Bibliography is from August 2012 through September 2021
Found 70 entries in the Bibliography.
Showing entries from 51 through 70
The effects of geomagnetic storms on electrons in Earth\textquoterights radiation belts
We use Van Allen Probes data to investigate the responses of 10s of keV to 2 MeV electrons throughout a broad range of the radiation belts (2.5 <= L <= 6.0) during 52 geomagnetic storms from the most recent solar maximum. Electron storm-time responses are highly dependent on both electron energy and L-shell. 10s of keV electrons typically have peak fluxes in the inner belt or near-Earth plasma sheet and fill the inner magnetosphere during storm main phases. ~100 to ~600 keV electrons are enhanced in up to 87\% of cases aroun ...
Turner, D.; O\textquoterightBrien, T.; Fennell, J.; Claudepierre, S.; Blake, J.; Kilpua, E.; Hietala, H.;
Published by: Geophysical Research Letters Published on: 07/2015
YEAR: 2015   DOI: 10.1002/2015GL064747
electrons; Van Allen Probes; Geomagnetic storms; Radiation belts
New model fit functions of the plasmapause location determined using THEMIS observations during the ascending phase of Solar Cycle 24
It is well known that the plasmapause is influenced by the solar wind and magnetospheric conditions. Empirical models of its location have been previously developed such as those by O\textquoterightBrien and Moldwin (2003) and Larsen et al. (2006). In this study, we identified the locations of the plasmapause using the plasma density data obtained from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites. We used the data for the period (2008\textendash2012) corresponding to the ascendi ...
Cho, Junghee; Lee, Dae-Young; Kim, Jin-Hee; Shin, Dae-Kyu; Kim, Kyung-Chan; Turner, Drew;
Published by: Journal of Geophysical Research: Space Physics Published on: 04/2015
YEAR: 2015   DOI: 10.1002/2015JA021030
Unraveling the drivers of the storm time radiation belt response
We present a new framework to study the time evolution and dynamics of the outer Van Allen belt electron fluxes. The framework is entirely based on the large-scale solar wind storm drivers and their substructures. The Van Allen Probe observations, revealing the electron flux behavior throughout the outer belt, are combined with continuous, long-term (over 1.5 solar cycles) geosynchronous orbit data set from GOES and solar wind measurements A superposed epoch analysis, where we normalize the timescales for each substructure ( ...
Kilpua, E.; Hietala, H.; Turner, D.; Koskinen, H.; Pulkkinen, T.; Rodriguez, J.; Reeves, G.; Claudepierre, S.; Spence, H.;
Published by: Geophysical Research Letters Published on: 04/2015
YEAR: 2015   DOI: 10.1002/2015GL063542
coronal mass ejections; Magnetic Storms; Radiation belts; solar wind storm drivers; stream interaction regions; Van Allen Probes
Spatial structure and temporal evolution of energetic particle injections in the inner magnetosphere during the 14 July 2013 substorm event.
Recent results by the Van Allen Probes mission showed that the occurrence of energetic ion injections inside geosynchronous orbit could be very frequent throughout the main phase of a geomagnetic storm. Understanding, therefore, the formation and evolution of energetic particle injections is critical in order to quantify their effect in the inner magnetosphere. We present a case study of a substorm event that occurred during a weak storm (Dst ~ - 40 nT) on 14 July 2013. Van Allen Probe B, inside geosynchronous orbit, observe ...
Gkioulidou, Matina; Ohtani, S.; Mitchell, D.; Ukhorskiy, A.; Reeves, G.; Turner, D.; Gjerloev, J.; e, Nos\; Koga, K.; Rodriguez, J.; Lanzerotti, L.;
Published by: Journal of Geophysical Research: Space Physics Published on: 02/2015
YEAR: 2015   DOI: 10.1002/2014JA020872
Energetic electron injections deep into the inner magnetosphere associated with substorm activity
From a survey of the first nightside season of NASA\textquoterights Van Allen Probes mission (Dec/2012 \textendash Sep/2013), 47 energetic (10s to 100s of keV) electron injection events were found at L-shells <= 4, all of which are deeper than any previously reported substorm-related injections. Preliminary details from these events are presented, including how: all occurred shortly after dipolarization signatures and injections were observed at higher L-shells; the deepest observed injection was at L~2.5; and, surprisingly, ...
Turner, D.; Claudepierre, S.; Fennell, J.; O\textquoterightBrien, T.; Blake, J.; Lemon, C.; Gkioulidou, M.; Takahashi, K.; Reeves, G.; Thaller, S.; Breneman, A.; Wygant, J.; Li, W.; Runov, A.; Angelopoulos, V.;
Published by: Geophysical Research Letters Published on: 02/2015
YEAR: 2015   DOI: 10.1002/2015GL063225
energetic particle injections; inner magnetosphere; Radiation belts; substorms; THEMIS; Van Allen Probes
Modeling CME-shock driven storms in 2012 - 2013: MHD-test particle simulations
The Van Allen Probes spacecraft have provided detailed observations of the energetic particles and fields environment for CME-shock driven storms in 2012 to 2013 which have now been modeled with MHD-test particle simulations. The Van Allen Probes orbital plane longitude moved from the dawn sector in 2012 to near midnight and pre-noon for equinoctial storms of 2013, providing particularly good measurements of the inductive electric field response to magnetopause compression for the 8 October 2013 CME-shock driven storm. An ab ...
Hudson, M.; Paral, J.; Kress, B.; Wiltberger, M.; Baker, D.; Foster, J.; Turner, D.; Wygant, J.;
Published by: Journal of Geophysical Research: Space Physics Published on: 01/2015
YEAR: 2015   DOI: 10.1002/2014JA020833
Evolution of relativistic outer belt electrons during an extended quiescent period
To effectively study steady loss due to hiss-driven precipitation of relativistic electrons in the outer radiation belt, it is useful to isolate this loss by studying a time of relatively quiet geomagnetic activity. We present a case of initial enhancement and slow, steady decay of 700 keV - 2 MeV electron populations in the outer radiation belt during an extended quiescent period from ~15 December 2012 - 13 January 2013. We incorporate particle measurements from a constellation of satellites, including the Colorado Student ...
Jaynes, A.; Li, X.; Schiller, Q.; Blum, L.; Tu, W.; Turner, D.; Ni, B.; Bortnik, J.; Baker, D.; Kanekal, S.; Blake, J.; Wygant, J.;
Published by: Journal of Geophysical Research: Space Physics Published on: 12/2014
YEAR: 2014   DOI: 10.1002/2014JA020125
electron lifetime; hiss waves; pitch angle scattering; precipitation loss; Radiation belts; Van Allen Probes
Modeling cross L shell impacts of magnetopause shadowing and ULF wave radial diffusion in the Van Allen belts
We present simulations of the outer electron radiation belt using a new ULF wave-driven radial diffusion model, including empirical representations of loss due to chorus and plasmaspheric hiss. With an outer boundary condition constrained by in situ electron flux observations, we focus on the impacts of magnetopause shadowing and outward radial diffusion in the heart of the radiation belt. Third invariant conserving solutions are combined to simulate the L shell and time dependence of the differential flux at a fixed energy. ...
Ozeke, Louis; Mann, Ian; Turner, Drew; Murphy, Kyle; Degeling, Alex; Rae, Jonathan; Milling, David;
Published by: Geophysical Research Letters Published on: 10/2014
YEAR: 2014   DOI: 10.1002/2014GL060787
magnetopause shadowing; Radiation belt; ULF wave radial diffusion
Quantifying the radiation belt seed population in the 17 March 2013 electron acceleration event
We present phase space density (PSD) observations using data from the Magnetic Electron Ion Spectrometer instrument on the Van Allen Probes for the 17 March 2013 electron acceleration event. We confirm previous results and quantify how PSD gradients depend on the first adiabatic invariant. We find a systematic difference between the lower-energy electrons (
Boyd, A.; Spence, H.; Claudepierre, S.; Fennell, J.; Blake, J.; Baker, D.; Reeves, G.; Turner, D.;
Published by: Geophysical Research Letters Published on: 04/2014
YEAR: 2014   DOI: 10.1002/2014GL059626
On the cause and extent of outer radiation belt losses during the 30 September 2012 dropout event
On 30 September 2012, a flux \textquotedblleftdropout\textquotedblright occurred throughout Earth\textquoterights outer electron radiation belt during the main phase of a strong geomagnetic storm. Using eight spacecraft from NASA\textquoterights Time History of Events and Macroscale Interactions during Substorms (THEMIS) and Van Allen Probes missions and NOAA\textquoterights Geostationary Operational Environmental Satellites constellation, we examined the full extent and timescales of the dropout based on particle energy, eq ...
Turner, D.; Angelopoulos, V.; Morley, S.; Henderson, M.; Reeves, G.; Li, W.; Baker, D.; Huang, C.-L.; Boyd, A.; Spence, H.; Claudepierre, S.; Blake, J.; Rodriguez, J.;
Published by: Journal of Geophysical Research: Space Physics Published on: 03/2014
YEAR: 2014   DOI: 10.1002/2013JA019446
dropouts; inner magnetosphere; loss; Radiation belts; relativistic electrons; Van Allen Probes
Competing source and loss mechanisms due to wave-particle interactions in Earth\textquoterights outer radiation belt during the 30 September to 3 October 2012 geomagnetic storm
Drastic variations of Earth\textquoterights outer radiation belt electrons ultimately result from various competing source, loss, and transport processes, to which wave-particle interactions are critically important. Using 15 spacecraft including NASA\textquoterights Van Allen Probes, THEMIS, and SAMPEX missions and NOAA\textquoterights GOES and POES constellations, we investigated the evolution of the outer belt during the strong geomagnetic storm of 30 September to 3 October 2012. This storm\textquoterights main phase drop ...
Turner, D.; Angelopoulos, V.; Li, W.; Bortnik, J.; Ni, B.; Ma, Q.; Thorne, R.; Morley, S.; Henderson, M.; Reeves, G.; Usanova, M.; Mann, I.; Claudepierre, S.; Blake, J.; Baker, D.; Huang, C.-L.; Spence, H.; Kurth, W.; Kletzing, C.; Rodriguez, J.;
Published by: Journal of Geophysical Research: Space Physics Published on: 03/2014
YEAR: 2014   DOI: 10.1002/jgra.v119.310.1002/2014JA019770
Effect of EMIC waves on relativistic and ultrarelativistic electron populations: Ground-based and Van Allen Probes observations
We study the effect of electromagnetic ion cyclotron (EMIC) waves on the loss and pitch angle scattering of relativistic and ultrarelativistic electrons during the recovery phase of a moderate geomagnetic storm on 11 October 2012. The EMIC wave activity was observed in situ on the Van Allen Probes and conjugately on the ground across the Canadian Array for Real-time Investigations of Magnetic Activity throughout an extended 18 h interval. However, neither enhanced precipitation of >0.7 MeV electrons nor reductions in Van All ...
Usanova, M.; Drozdov, A.; Orlova, K.; Mann, I.; Shprits, Y.; Robertson, M.; Turner, D.; Milling, D.; Kale, A.; Baker, D.; Thaller, S.; Reeves, G.; Spence, H.; Kletzing, C.; Wygant, J.;
Published by: Geophysical Research Letters Published on: 03/2014
YEAR: 2014   DOI: 10.1002/2013GL059024
Space science: Near-Earth space shows its stripes
Using some of the first scientific satellites put into orbit during the late 1950s, teams led by physicists James Van Allen in the United States and Sergei Vernov in the Soviet Union independently reported1, 2 on defined regions of radiation in near-Earth space. These regions came to be known as Earth\textquoterights radiation belts, and they represent the first major scientific discovery of the space age. However, despite decades of study, many questions in radiation-belt physics remain unanswered, mostly concerning the nat ...
Published by: Nature Published on: 03/2014
YEAR: 2014   DOI: 10.1038/507308a
Chorus waves and spacecraft potential fluctuations: Evidence for wave-enhanced photoelectron escape
Chorus waves are important for electron energization and loss in Earth\textquoterights radiation belts and inner magnetosphere. Because the amplitude and spatial distribution of chorus waves can be strongly influenced by plasma density fluctuations and spacecraft floating potential can be a diagnostic of plasma density, the relationship between measured potential and chorus waves is examined using Van Allen Probes data. While measured potential and chorus wave electric fields correlate strongly, potential fluctuation propert ...
Malaspina, D.; Ergun, R.; Sturner, A.; Wygant, J.; Bonnell, J; Breneman, A.; Kersten, K.;
Published by: Geophysical Research Letters Published on: 01/2014
YEAR: 2014   DOI: 10.1002/2013GL058769
A nonstorm time enhancement of relativistic electrons in the outer radiation belt
Despite the lack of a geomagnetic storm (based on the Dst index), relativistic electron fluxes were enhanced over 2.5 orders of magnitude in the outer radiation belt in 13 h on 13\textendash14 January 2013. The unusual enhancement was observed by Magnetic Electron Ion Spectrometer (MagEIS), onboard the Van Allen Probes; Relativistic Electron and Proton Telescope Integrated Little Experiment, onboard the Colorado Student Space Weather Experiment; and Solid State Telescope, onboard Time History of Events and Macroscale Interac ...
Schiller, Quintin; Li, Xinlin; Blum, Lauren; Tu, Weichao; Turner, Drew; Blake, J.;
Published by: Geophysical Research Letters Published on: 01/2014
YEAR: 2014   DOI: 10.1002/2013GL058485
Unusual stable trapping of the ultrarelativistic electrons in the Van Allen radiation belts
Radiation in space was the first discovery of the space age. Earth\textquoterights radiation belts consist of energetic particles that are trapped by the geomagnetic field and encircle the planet1. The electron radiation belts usually form a two-zone structure with a stable inner zone and a highly variable outer zone, which forms and disappears owing to wave\textendashparticle interactions on the timescale of a day, and is strongly influenced by the very-low-frequency plasma waves. Recent observations revealed a third radiat ...
Shprits, Yuri; Subbotin, Dmitriy; Drozdov, Alexander; Usanova, Maria; Kellerman, Adam; Orlova, Ksenia; Baker, Daniel; Turner, Drew; Kim, Kyung-Chan;
Published by: Nature Physics Published on: 11/2013
YEAR: 2013   DOI: 10.1038/nphys2760
First Results from CSSWE CubeSat: Characteristics of Relativistic Electrons in the Near-Earth Environment During the October 2012 Magnetic Storms
Measurements from the Relativistic Electron and Proton Telescope integrated little experiment (REPTile) on board the Colorado Student Space Weather Experiment (CSSWE) CubeSat mission, which was launched into a highly inclined (65\textdegree) low Earth orbit, are analyzed along with measurements from the Relativistic Electron and Proton Telescope (REPT) and the Magnetic Electron Ion Spectrometer (MagEIS) instruments aboard the Van Allen Probes, which are in a low inclination (10\textdegree) geo-transfer-like orbit. Both REPT ...
Li, X.; Schiller, Q.; Blum, L.; Califf, S.; Zhao, H.; Tu, W.; Turner, D.; Gerhardt, D.; Palo, S.; Kanekal, S.; Baker, D.; Fennell, J.; Blake, J.; Looper, M.; Reeves, G.; Spence, H.;
Published by: Journal of Geophysical Research: Space Physics Published on: 10/2013
YEAR: 2013   DOI: 10.1002/2013JA019342
Electron Acceleration in the Heart of the Van Allen Radiation Belts
The Van Allen radiation belts contain ultrarelativistic electrons trapped in Earth\textquoterights magnetic field. Since their discovery in 1958, a fundamental unanswered question has been how electrons can be accelerated to such high energies. Two classes of processes have been proposed: transport and acceleration of electrons from a source population located outside the radiation belts (radial acceleration) or acceleration of lower-energy electrons to relativistic energies in situ in the heart of the radiation belts (local ...
Reeves, G.; Spence, H.; Henderson, M.; Morley, S.; Friedel, R.; Funsten, H.; Baker, D.; Kanekal, S.; Blake, J.; Fennell, J.; Claudepierre, S.; Thorne, R.; Turner, D.; Kletzing, C.; Kurth, W.; Larsen, B.; Niehof, J.;
Published by: Science Published on: 07/2013
YEAR: 2013   DOI: 10.1126/science.1237743
Evolution and slow decay of an unusual narrow ring of relativistic electrons near L ~ 3.2 following the September 2012 magnetic storm
A quantitative analysis is performed on the decay of an unusual ring of relativistic electrons between 3 and 3.5 RE, which was observed by the Relativistic Electron Proton Telescope instrument on the Van Allen probes. The ring formed on 3 September 2012 during the main phase of a magnetic storm due to the partial depletion of the outer radiation belt for L > 3.5, and this remnant belt of relativistic electrons persisted at energies above 2 MeV, exhibiting only slow decay, until it was finally destroyed during another magneti ...
Thorne, R.; Li, W.; Ni, B.; Ma, Q.; Bortnik, J.; Baker, D.; Spence, H.; Reeves, G.; Henderson, M.; Kletzing, C.; Kurth, W.; Hospodarsky, G.; Turner, D.; Angelopoulos, V.;
Published by: Geophysical Research Letters Published on: 06/2013
YEAR: 2013   DOI: 10.1002/grl.50627
Explaining sudden losses of outer radiation belt electrons during geomagnetic storms
The Van Allen radiation belts were first discovered in 1958 by the Explorer series of spacecraft1. The dynamic outer belt consists primarily of relativistic electrons trapped by the Earth\textquoterights magnetic field. Magnetospheric processes driven by the solar wind2 cause the electron flux in this belt to fluctuate substantially over timescales ranging from minutes to years3. The most dramatic of these events are known as flux \textquoterightdropouts\textquoteright and often occur during geomagnetic storms. During such a ...
Turner, Drew; Shprits, Yuri; Hartinger, Michael; Angelopoulos, Vassilis;
Published by: Nature Physics Published on: 01/2012
YEAR: 2012   DOI: 10.1038/nphys2185