Bibliography



Found 568 entries in the Bibliography.


Showing entries from 1 through 50


2021

Energetic Electron Precipitation Observed by FIREBIRD-II Potentially Driven by EMIC Waves: Location, Extent, and Energy Range from a Multi-Event Analysis

Abstract We evaluate the location, extent and energy range of electron precipitation driven by ElectroMagnetic Ion Cyclotron (EMIC) waves using coordinated multi-satellite observations from near-equatorial and Low-Earth-Orbit (LEO) missions. Electron precipitation was analyzed using the Focused Investigations of Relativistic Electron Burst Intensity, Range and Dynamics (FIREBIRD-II) CubeSats, in conjunction either with typical EMIC-driven precipitation signatures observed by Polar Orbiting Environmental Satellites (POES) or ...

Capannolo, L.; Li, W.; Spence, H.; Johnson, A.; Shumko, M.; Sample, J.; Klumpar, D.;

YEAR: 2021     DOI: https://doi.org/10.1029/2020GL091564

electron precipitation; EMIC waves; inner magnetosphere; electron losses; proton precipitation; wave-particle interactions; Van Allen Probes

A Case Study of Transversely Heated Low-Energy Helium Ions by EMIC Waves in the Plasmasphere

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

Kim, Khan-Hyuk; Kwon, Hyuck-Jin; Lee, Junhyun; Jin, Ho; Seough, Jungjoon;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA028560

Van Allen Probes

Observations of Particle Loss due to Injection-Associated EMIC Waves

AbstractWe report on observations of electromagnetic ion cyclotron (EMIC) waves and their interactions with injected ring current particles and high energy radiation belt electrons. The magnetic field experiment aboard the twin Van Allen Probes spacecraft measured EMIC waves near L = 5.5 − 6. Particle data from the spacecraft show that the waves were associated with particle injections. The wave activity was also observed by a ground-based magnetometer near the spacecraft geomagnetic footprint over a more extensive tempora ...

Kim, Hyomin; Schiller, Quintin; Engebretson, Mark; Noh, Sungjun; Kuzichev, Ilya; Lanzerotti, Louis; Gerrard, Andrew; Kim, Khan-Hyuk; Lessard, Marc; Spence, Harlan; Lee, Dae-Young; Matzka, Jürgen; Fromm, Tanja;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA028503

EMIC waves; ring current; Radiation belt; wave particle interaction; injection; Particle precipitation; Van Allen Probes

Observations of Particle Loss due to Injection-Associated EMIC Waves

AbstractWe report on observations of electromagnetic ion cyclotron (EMIC) waves and their interactions with injected ring current particles and high energy radiation belt electrons. The magnetic field experiment aboard the twin Van Allen Probes spacecraft measured EMIC waves near L = 5.5 − 6. Particle data from the spacecraft show that the waves were associated with particle injections. The wave activity was also observed by a ground-based magnetometer near the spacecraft geomagnetic footprint over a more extensive tempora ...

Kim, Hyomin; Schiller, Quintin; Engebretson, Mark; Noh, Sungjun; Kuzichev, Ilya; Lanzerotti, Louis; Gerrard, Andrew; Kim, Khan-Hyuk; Lessard, Marc; Spence, Harlan; Lee, Dae-Young; Matzka, Jürgen; Fromm, Tanja;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA028503

EMIC waves; ring current; Radiation belt; wave particle interaction; injection; Particle precipitation; Van Allen Probes

Observations of Particle Loss due to Injection-Associated EMIC Waves

AbstractWe report on observations of electromagnetic ion cyclotron (EMIC) waves and their interactions with injected ring current particles and high energy radiation belt electrons. The magnetic field experiment aboard the twin Van Allen Probes spacecraft measured EMIC waves near L = 5.5 − 6. Particle data from the spacecraft show that the waves were associated with particle injections. The wave activity was also observed by a ground-based magnetometer near the spacecraft geomagnetic footprint over a more extensive tempora ...

Kim, Hyomin; Schiller, Quintin; Engebretson, Mark; Noh, Sungjun; Kuzichev, Ilya; Lanzerotti, Louis; Gerrard, Andrew; Kim, Khan-Hyuk; Lessard, Marc; Spence, Harlan; Lee, Dae-Young; Matzka, Jürgen; Fromm, Tanja;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA028503

EMIC waves; ring current; Radiation belt; wave particle interaction; injection; Particle precipitation; Van Allen Probes

Multi-Point Observations of Quasiperiodic Emission Intensification and Effects on Energetic Electron Precipitation

AbstractThe two Van Allen Probes simultaneously recorded a coherently modulated quasiperiodic (QP) emission that persisted for 3 hours. The magnetic field pulsation at the locations of the two satellites showed a substantial difference, and their frequencies were close to but did not exactly match the repetition frequency of QP emissions for most of the time, suggesting that those coherent QP emissions probably originated from a common source, which then propagated over a broad area in the magnetosphere. The QP emissions wer ...

Li, Jinxing; Bortnik, Jacob; Ma, Qianli; Li, Wen; Shen, Xiaochen; Nishimura, Yukitoshi; An, Xin; Thaller, Scott; Breneman, Aaron; Wygant, John; Kurth, William; Hospodarsky, George; Hartley, David; Reeves, Geoffrey; Funsten, Herbert; Blake, Bernard; Spence, Harlan; Baker, Daniel;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA028484

quasiperiodic emissions; electron precipitation; Radiation belt; chorus waves; Van Allen Probes; ULF wave

Multi-Point Observations of Quasiperiodic Emission Intensification and Effects on Energetic Electron Precipitation

AbstractThe two Van Allen Probes simultaneously recorded a coherently modulated quasiperiodic (QP) emission that persisted for 3 hours. The magnetic field pulsation at the locations of the two satellites showed a substantial difference, and their frequencies were close to but did not exactly match the repetition frequency of QP emissions for most of the time, suggesting that those coherent QP emissions probably originated from a common source, which then propagated over a broad area in the magnetosphere. The QP emissions wer ...

Li, Jinxing; Bortnik, Jacob; Ma, Qianli; Li, Wen; Shen, Xiaochen; Nishimura, Yukitoshi; An, Xin; Thaller, Scott; Breneman, Aaron; Wygant, John; Kurth, William; Hospodarsky, George; Hartley, David; Reeves, Geoffrey; Funsten, Herbert; Blake, Bernard; Spence, Harlan; Baker, Daniel;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA028484

quasiperiodic emissions; electron precipitation; Radiation belt; chorus waves; Van Allen Probes; ULF wave

2020

Evolution of pitch angle distributions of relativistic electrons during geomagnetic storms: Van Allen Probes Observations

We present a study analyzing relativistic and ultra relativistic electron energization and the evolution of pitch angle distributions using data from the Van Allen Probes. We study the connection between energization and isotropization to determine if there is a coherence across storms and across energies. Pitch angle distributions are fit with a J0sinnθ function, and the variable ’n’ is characterized as the pitch angle index and tracked over time. Our results show that, consistently across all storms with ultra relativ ...

Greeley, Ashley; Kanekal, Shrikanth; Sibeck, David; Schiller, Quintin; Baker, Daniel;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028335

pitch angle distributions; relativistic electrons; ultra relativistic electrons; Van Allen Probes; pitch angle distribution evolution; anisotropic electrons

Evolution of pitch angle distributions of relativistic electrons during geomagnetic storms: Van Allen Probes Observations

We present a study analyzing relativistic and ultra relativistic electron energization and the evolution of pitch angle distributions using data from the Van Allen Probes. We study the connection between energization and isotropization to determine if there is a coherence across storms and across energies. Pitch angle distributions are fit with a J0sinnθ function, and the variable ’n’ is characterized as the pitch angle index and tracked over time. Our results show that, consistently across all storms with ultra relativ ...

Greeley, Ashley; Kanekal, Shrikanth; Sibeck, David; Schiller, Quintin; Baker, Daniel;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028335

pitch angle distributions; relativistic electrons; ultra relativistic electrons; Van Allen Probes; pitch angle distribution evolution; anisotropic electrons

The Implications of Temporal Variability in Wave-Particle Interactions in Earth s Radiation Belts

Changes in electron flux in Earth s outer radiation belt can be modeled using a diffusion-based framework. Diffusion coefficients D for such models are often constructed from statistical averages of observed inputs. Here, we use stochastic parameterization to investigate the consequences of temporal variability in D. Variability time scales are constrained using Van Allen Probe observations. Results from stochastic parameterization experiments are compared with experiments using D constructed from averaged inputs and an aver ...

Watt, C.; Allison, H.; Thompson, R.; Bentley, S.; Meredith, N.; Glauert, S.; Horne, R.; Rae, I.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL089962

probabilistic methods; stochastic parameterization; Van Allen Probes

Detection of Hertz Frequency Multiharmonic Field Line Resonances at Low-L (L = 1.1–1.5) During Van Allen Probe Perigee Passes

We present new and previously unreported in situ observations of Hertz frequency multiharmonic mode field line resonances detected by the Electric Field and Waves instrument on-board the NASA Van Allen probes during low-L perigee passes. Spectral analysis of the spin-plane electric field data reveals the waves in numerous perigee passes, in sequential passes of probes A and B, and with harmonic frequency structures from ∼0.5 to 3.5 Hz which vary with L-shell, altitude, and from day-to-day. Comparing the observations to wa ...

Lena, F.; Ozeke, L.; Wygant, J.; Tian, S.; Breneman, A.; Mann, I.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL090632

Field line resonance; Ionosphere; magneto-seismology; Magnetosphere; plasmasphere; standing Alfvén waves; Van Allen Probes

Inner Magnetospheric Response to the Interplanetary Magnetic Field By Component: Van Allen Probes and Arase Observations

We utilize 17 years of combined Van Allen Probes and Arase data to statistically analyze the response of the inner magnetosphere to the orientation of the interplanetary magnetic field (IMF) By component. Past studies have demonstrated that the IMF By component introduces a similarly oriented By component into the magnetosphere. However, these studies have tended to focus on field lines in the magnetotail only reaching as close to the Earth as the geosynchronous orbit. By exploiting data from these inner magnetospheric spac ...

Case, N.; Hartley, D.; Grocott, A.; Miyoshi, Y.; Matsuoka, A.; Imajo, S.; Kurita, S.; Shinohara, I.; Teramoto, M.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028765

By; y-component; inner magnetosphere; IMF; response; Van Allen Probes

Formation of the Low-Energy “Finger” Ion Spectral Structure Near the Inner Edge of the Plasma Sheet

We present a case study of the H+, He+, and O+ low-energy “finger” structure observed by the Van Allen Probe A Helium, Oxygen, Proton, and Electron (HOPE) spectrometer on 26 October 2016. This structure, whose characteristic energy is from approximately tens of eV to a few keV, looks like a “finger” that is rich in O+ and He+, faint in H+ on an energy-time spectrogram. By using the Space Weather Modeling Framework (SWMF) and Weimer05 electric fields, combined with a dipole or more self-consistent magnetohydrodynamic ...

Wang, Y.; Kistler, L.; Mouikis, C.; Zhang, J.; Lu, J; Welling, D.; Rastaetter, L.; Bingham, S.; Jin, Y.; Wang, L.; Miyoshi, Y.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL089875

Van Allen Probes

Long-Term Dropout of Relativistic Electrons in the Outer Radiation Belt During Two Sequential Geomagnetic Storms

On 31 January 2016, the flux of >2 MeV electrons observed by Geostationary Operational Environmental Satellite (GOES)-13 dropped to the background level during a minor storm main phase (−48 nT). Then, a second storm (−53 nT) occurred on 2 February; during the 3 days after its main phase, the flux remained at background level. Using data from various instruments on the GOES, Polar Operational Environmental Satellites (POES), Radiation Belt Storm Probes (RBSP), Meteor-M2, and Fengyun-series spacecraft, we study this long ...

Wu, H.; Chen, T.; Kalegaev, V.; Panasyuk, M.; Vlasova, N.; Duan, S.; Zhang, X.; He, Z.; Luo, J.; Wang, C.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028098

Radiation belt; relativistic electron dropout; Geomagnetic storm; Van Allen Probes

Cross-Scale Quantification of Storm-Time Dayside Magnetospheric Magnetic Flux Content

A clear understanding of storm-time magnetospheric dynamics is essential for a reliable storm forecasting capability. The dayside magnetospheric response to an interplanetary coronal mass ejection (ICME; dynamic pressure Pdyn > 20 nPa and storm-time index SYM-H < −150 nT) is investigated using in situ OMNI, Geotail, Cluster, MMS, GOES, Van Allen Probes, and THEMIS measurements. The dayside magnetic flux content is directly quantified from in situ magnetic field measurements at different radial distances. The arrival ...

Akhavan-Tafti, M.; Fontaine, D.; Slavin, J.; Le Contel, O.; Turner, D.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028027

interplanetary coronal mass ejection; magnetic flux quantification; cross-scale observations; flux transfer event; Dungey cycle; Geomagnetic storm; Van Allen Probes

First Direct Observations of Propagation of Discrete Chorus Elements From the Equatorial Source to Higher Latitudes, Using the Van Allen Probes and Arase Satellites

Whistler mode chorus waves have recently been established as the most likely candidate for scattering relativistic electrons to produce the electron microbursts observed by low altitude satellites and balloons. These waves would have to propagate from the equatorial source region to significantly higher magnetic latitude in order to scatter electrons of these relativistic energies. This theoretically proposed propagation has never been directly observed. We present the first direct observations of the same discrete rising to ...

Colpitts, Chris; Miyoshi, Yoshizumi; Kasahara, Yoshiya; Delzanno, Gian; Wygant, John; Cattell, Cynthia; Breneman, Aaron; Kletzing, Craig; Cunningham, Greg; Hikishima, Mitsuru; Matsuda, Shoya; Katoh, Yuto; Ripoll, Jean-Francois; Shinohara, Iku; Matsuoka, Ayako;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028315

Chorus; wave; propagation; Simultaneous observations; Radiation belt; Van Allen Probes

Spatial Extent of Quasiperiodic Emissions Simultaneously Observed by Arase and Van Allen Probes on 29 November 2018

Recent availability of a considerable amount of satellite and ground-based data has allowed us to analyze rare conjugated events where extremely low and very low frequency waves from the same source region are observed in different locations. Here, we report a quasiperiodic (QP) emission, showing one-to-one correspondence, observed by three satellites in space (Arase and the Van Allen Probes) and a ground station. The main event was on 29 November 2018 from 12:06 to 13:08 UT during geomagnetically quiet times. Using the po ...

Martinez-Calderon, C.; Němec, F.; Katoh, Y.; Shiokawa, K.; Kletzing, C.; Hospodarsky, G.; Santolik, O.; Kasahara, Y.; Matsuda, S.; Kumamoto, A.; Tsuchiya, F.; Matsuoka, A.; Shoji, M.; Teramoto, M.; Kurita, S.; Miyoshi, Y.; Ozaki, M.; Nishitani, N.; Oinats, A.; Kurkin, V.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028126

VLF/ELF; spatial extent; conjugated events; ERG; RBSP; quasiperiodic emissions; Van Allen Probes

Global Survey of Plasma Sheet Electron Precipitation due to Whistler Mode Chorus Waves in Earth s Magnetosphere

Whistler mode chorus waves can scatter plasma sheet electrons into the loss cone and produce the Earth s diffuse aurora. Van Allen Probes observed plasma sheet electron injections and intense chorus waves on 24 November 2012. We use quasilinear theory to calculate the precipitating electron fluxes, demonstrating that the chorus waves could lead to high differential energy fluxes of precipitating electrons with characteristic energies of 10–30 keV. Using this method, we calculate the precipitating electron flux from 2012 t ...

Ma, Q.; Connor, H.; Zhang, X.-J.; Li, W.; Shen, X.-C.; Gillespie, D.; Kletzing, C.; Kurth, W.; Hospodarsky, G.; Claudepierre, S.; Reeves, G.; Spence, H.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL088798

Chorus wave; electron precipitation; plasma sheet electron; Van Allen Probes observation; Van Allen Probes

Global Survey of Plasma Sheet Electron Precipitation due to Whistler Mode Chorus Waves in Earth s Magnetosphere

Whistler mode chorus waves can scatter plasma sheet electrons into the loss cone and produce the Earth s diffuse aurora. Van Allen Probes observed plasma sheet electron injections and intense chorus waves on 24 November 2012. We use quasilinear theory to calculate the precipitating electron fluxes, demonstrating that the chorus waves could lead to high differential energy fluxes of precipitating electrons with characteristic energies of 10–30 keV. Using this method, we calculate the precipitating electron flux from 2012 t ...

Ma, Q.; Connor, H.; Zhang, X.-J.; Li, W.; Shen, X.-C.; Gillespie, D.; Kletzing, C.; Kurth, W.; Hospodarsky, G.; Claudepierre, S.; Reeves, G.; Spence, H.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL088798

Chorus wave; electron precipitation; plasma sheet electron; Van Allen Probes observation; Van Allen Probes

Experimental Determination of the Conditions Associated With “Zebra Stripe” Pattern Generation in the Earth s Inner Radiation Belt and Slot Region

The “zebra stripes” are peaks and valleys commonly present in the spectrograms of energetic particles trapped in the Earth s inner belt and slot region. Several theories have been proposed over the years to explain their generation, structure, and evolution. Yet, the plausibility of various theories has not been tested due to a historical lack of ground truth, including in situ electric field measurements. In this work, we leverage the new visibility offered by the database of Van Allen Probes electric drift measurements ...

Lejosne, Solène; Mozer, Forrest;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA027889

zebra stripes; superposed epoch analysis; prompt penetration electric fields; Inner radiation belt; substorm; Van Allen Probes

Defining Radiation Belt Enhancement Events Based on Probability Distributions

We present a methodology to define moderate, strong, and intense space weather events based on probability distributions. We have illustrated this methodology using a long-duration, uniform data set of 1.8–3.5 MeV electron fluxes from multiple LANL geosynchronous satellite instruments, but a strength of this methodology is that it can be applied uniformly to heterogeneous data sets. It allows quantitative comparison of data sets with different energies, units, orbits, and so forth. The methodology identifies a range of ti ...

Reeves, Geoffrey; Vandegriff, Elizabeth; Niehof, Jonathan; Morley, Steven; Cunningham, Gregory; Henderson, Michael; Larsen, Brian;

YEAR: 2020     DOI: https://doi.org/10.1029/2020SW002528

Radiation belts; methods; geosynchronous; energetic particles; hazards; Solar Cycle; Van Allen Probes

Conjugate Observations of Quasiperiodic Emissions by the Van Allen Probes Spacecraft and Ground-Based Station Kannuslehto

Whistler mode waves observed in the Earth s inner magnetosphere at frequencies between about 0.5 and 4 kHz which exhibit a nearly periodic time modulation of the wave intensity are called quasiperiodic (QP) emissions. Conjugate measurements of QP events at several different locations can be used to estimate their spatial extent and spatiotemporal variability. Results obtained using conjugate QP measurements provided by the ground-based station Kannuslehto (L≈5.5) and the Van Allen Probes spacecraft (L shells between about ...

Bezděková, B.; Němec, F.; Manninen, J.; Hospodarsky, G.; Santolik, O.; Kurth, W.; Hartley, D.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA027793

Van Allen Probes

Global ENA Imaging and In Situ Observations of Substorm Dipolarization on 10 August 2016

Abstract This paper presents the first combined use of data from Magnetospheric Multiscale (MMS), Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS), and Van Allen Probes (RBSP) to study the 10 August 2016 magnetic dipolarization. We report the first correlation of MMS tail observations with TWINS energetic neutral atom (ENA) images of the ring current (RC). We analyze 15-min, 1° TWINS 2 images in 1–50 keV energy bins. To characterize the high-altitude RC we extract peak ENA flux from L= 2.5 to 5 in the postmid ...

Goldstein, J.; Valek, P.; McComas, D.; Redfern, J.; Spence, H.; Skoug, R.; Larsen, B.; Reeves, G.; Nakamura, R.;

YEAR: 2020     DOI: 10.1029/2019JA027733

substorm dipolarization; cross-scale physics; imaging; multipoint in situ; ring current; Van Allen Probes

Simultaneous Observations of Electromagnetic Ion Cyclotron (EMIC) Waves and Pitch Angle Scattering During a Van Allen Probes Conjunction

Abstract On 22 December 2015, the two Van Allen Probes observed two sets of electromagnetic ion cyclotron (EMIC) wave bursts during a close conjunction when both Probe A and Probe B were separated by 0.57 to 0.68 RE. The EMIC waves occurred during an active period in the recovery phase of a coronal mass ejection-driven geomagnetic storm. Both spacecraft observed EMIC wave bursts that had similar spatial structure within a 1–2 min time delay. The EMIC waves occurred outside the plasmasphere, within ΔL ≈ 1–2 of the ...

Sigsbee, K.; Kletzing, C. A.; Faden, J.; Jaynes, A. N.; Reeves, G.; Jahn, J.-M.;

YEAR: 2020     DOI: 10.1029/2019JA027424

EMIC waves; Plasmapause; Proton Anisotropy; Storm Recovery Phase; Van Allen Probes; pitch angle scattering

Bayesian Inference of Quasi-Linear Radial Diffusion Parameters using Van Allen Probes

Abstract The Van Allen radiation belts in the magnetosphere have been extensively studied using models based on radial diffusion theory, which is derived from a quasi-linear approach with prescribed inner and outer boundary conditions. The 1D diffusion model requires the knowledge of a diffusion coefficient and an electron loss timescale, which is typically parameterized in terms of various quantities such as the spatial (L) coordinate or a geomagnetic index (e.g., Kp). These terms are typically empirically derived, not dire ...

Sarma, Rakesh; Chandorkar, Mandar; Zhelavskaya, Irina; Shprits, Yuri; Drozdov, Alexander; Camporeale, Enrico;

YEAR: 2020     DOI: 10.1029/2019JA027618

radial diffusion; Magnetosphere; Bayesian inference; Van Allen radiation belt; Van Allen Probes

Whistler Mode Quasiperiodic Emissions: Contrasting Van Allen Probes and DEMETER Occurrence Rates

Abstract Quasiperiodic emissions are magnetospheric whistler mode waves at frequencies between about 0.5 and 4 kHz which exhibit a nearly periodic time modulation of the wave intensity. We use large data sets of events observed by the Van Allen Probes in the equatorial region at larger radial distances and by the low-altitude DEMETER spacecraft. While Van Allen Probes observe the events at all local times and longitudes, DEMETER observations are limited nearly exclusively to the daytime and significantly less frequent at the ...

Němec, F.; Santolik, O.; Hospodarsky, G.; Hajoš, M.; Demekhov, A.; Kurth, W.; Parrot, M.; Hartley, D.;

YEAR: 2020     DOI: 10.1029/2020JA027918

quasiperiodic emissions; QP emissions; DEMETER; RBSP; Van Allen Probes

Global ENA Imaging and In Situ Observations of Substorm Dipolarization on 10 August 2016

This paper presents the first combined use of data from Magnetospheric Multiscale (MMS), Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS), and Van Allen Probes (RBSP) to study the 10 August 2016 magnetic dipolarization. We report the first correlation of MMS tail observations with TWINS energetic neutral atom (ENA) images of the ring current (RC). We analyze 15-min, 1° TWINS 2 images in 1–50 keV energy bins. To characterize the high-altitude RC we extract peak ENA flux from L= 2.5 to 5 in the postmidnight sec ...

Goldstein, J.; Valek, P.; McComas, D.; Redfern, J.; Spence, H.; Skoug, R.; Larsen, B.; Reeves, G.; Nakamura, R.;

YEAR: 2020     DOI: https://doi.org/10.1029/2019JA027733

substorm dipolarization; cross-scale physics; imaging; multipoint in situ; ring current

Simultaneous Observations of Electromagnetic Ion Cyclotron (EMIC) Waves and Pitch Angle Scattering During a Van Allen Probes Conjunction

On 22 December 2015, the two Van Allen Probes observed two sets of electromagnetic ion cyclotron (EMIC) wave bursts during a close conjunction when both Probe A and Probe B were separated by 0.57 to 0.68 RE. The EMIC waves occurred during an active period in the recovery phase of a coronal mass ejection-driven geomagnetic storm. Both spacecraft observed EMIC wave bursts that had similar spatial structure within a 1–2 min time delay. The EMIC waves occurred outside the plasmasphere, within ΔL ≈ 1–2 of the plasmapau ...

Sigsbee, K.; Kletzing, C. A.; Faden, J.; Jaynes, A. N.; Reeves, G.; Jahn, J.-M.;

YEAR: 2020     DOI: https://doi.org/10.1029/2019JA027424

EMIC waves; Plasmapause; Proton Anisotropy; Storm Recovery Phase; Van Allen Probes; pitch angle scattering

Bayesian Inference of Quasi-Linear Radial Diffusion Parameters using Van Allen Probes

The Van Allen radiation belts in the magnetosphere have been extensively studied using models based on radial diffusion theory, which is derived from a quasi-linear approach with prescribed inner and outer boundary conditions. The 1D diffusion model requires the knowledge of a diffusion coefficient and an electron loss timescale, which is typically parameterized in terms of various quantities such as the spatial (L) coordinate or a geomagnetic index (e.g., Kp). These terms are typically empirically derived, not directly meas ...

Sarma, Rakesh; Chandorkar, Mandar; Zhelavskaya, Irina; Shprits, Yuri; Drozdov, Alexander; Camporeale, Enrico;

YEAR: 2020     DOI: https://doi.org/10.1029/2019JA027618

radial diffusion; Magnetosphere; Bayesian inference; Van Allen radiation belt; Van Allen Probes

Whistler Mode Quasiperiodic Emissions: Contrasting Van Allen Probes and DEMETER Occurrence Rates

Quasiperiodic emissions are magnetospheric whistler mode waves at frequencies between about 0.5 and 4 kHz which exhibit a nearly periodic time modulation of the wave intensity. We use large data sets of events observed by the Van Allen Probes in the equatorial region at larger radial distances and by the low-altitude DEMETER spacecraft. While Van Allen Probes observe the events at all local times and longitudes, DEMETER observations are limited nearly exclusively to the daytime and significantly less frequent at the longitud ...

Němec, F.; Santolik, O.; Hospodarsky, G.; Hajoš, M.; Demekhov, A.; Kurth, W.; Parrot, M.; Hartley, D.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA027918

quasiperiodic emissions; QP emissions; DEMETER; RBSP; Van Allen Probes

A Multi-Instrument Approach to Determining the Source-Region Extent of EEP-Driving EMIC Waves

Abstract Recent years have seen debate regarding the ability of electromagnetic ion cyclotron (EMIC) waves to drive EEP (energetic electron precipitation) into the Earth s atmosphere. Questions still remain regarding the energies and rates at which these waves are able to interact with electrons. Many studies have attempted to characterize these interactions using simulations; however, these are limited by a lack of precise information regarding the spatial scale size of EMIC activity regions. In this study we examine a fort ...

Hendry, A.; Santolik, O.; Miyoshi, Y.; Matsuoka, A.; Rodger, C.; Clilverd, M.; Kletzing, C.; Shoji, M.; Shinohara, I.;

YEAR: 2020     DOI: 10.1029/2019GL086599

EMIC waves; electron precipitation; subionospheric VLF; Van Allen Probes; AARDDVARK; Arase

Fine Harmonic Structure of Equatorial Noise with a Quasiperiodic Modulation

Abstract Equatorial noise emissions (fast magnetosonic waves) are electromagnetic waves observed routinely in the equatorial region of the inner magnetosphere. They propagate with wave vectors nearly perpendicular to the ambient magnetic field; that is, they are limited to frequencies below the lower hybrid frequency. The waves are generated by instabilities of ring-like proton distribution functions, which result in their fine harmonic structure with intensity maxima close to harmonics of the proton cyclotron frequency in t ...

Němec, F.; Tomori, A.; Santolik, O.; Boardsen, S.; Hospodarsky, G.; Kurth, W.; Pickett, J.; Kletzing, C.;

YEAR: 2020     DOI: 10.1029/2019JA027509

equatorial noise; Fast Magnetosonic Waves; quasiperiodic modulation; Van Allen Probes

Analysis of Electric and Magnetic Lightning-Generated Wave Amplitudes Measured by the Van Allen Probes

Abstract We provide a statistical analysis of both electric and magnetic field wave amplitudes of very low frequency lightning-generated waves (LGWs) based on the equivalent of 11.5 years of observations made by the Van Allen Probes encompassing ~24.6 × 106 survey mode measurements. We complement this analysis with data from the ground-based World Wide Lightning Location Network to explore differences between satellite and ground-based measurements. LGW mean amplitudes are found to be low compared with other whistler mod ...

Ripoll, J.-F.; Farges, T.; Malaspina, D.; Lay, E.; Cunningham, G.; Hospodarsky, G.; Kletzing, C.; Wygant, J.;

YEAR: 2020     DOI: 10.1029/2020GL087503

lightning-generated waves; electric wave power; magnetic wave power; WWLLN database; Radiation belts; Van Allen Probes

Determining plasmaspheric density from the upper hybrid resonance and from the spacecraft potential: How do they compare?

The plasmasphere is a critical region of the magnetosphere. It is important for the evolution of Earth\textquoterights radiation belts. Waves in the plasmasphere interior (hiss) and vicinity (EMIC, chorus) help control the acceleration and loss of radiation belt particles. Thus, understanding the extent, structure, content, and dynamics of the plasmasphere is crucial to understanding radiation belt losses. The Van Allen Probes mission uses two methods to determine the total plasma density. First, the upper hybrid resonance ( ...

Jahn, J.-M.; Goldstein, J.; Kurth, W.S.; Thaller, S.; De Pascuale, S.; Wygant, J.; Reeves, G.D.; Spence, H.E.;

YEAR: 2020     DOI: 10.1029/2019JA026860

cold plasma density; plasmasphere; spacecraft charging; Van Allen Probes; wave resonances

Determining plasmaspheric density from the upper hybrid resonance and from the spacecraft potential: How do they compare?

The plasmasphere is a critical region of the magnetosphere. It is important for the evolution of Earth\textquoterights radiation belts. Waves in the plasmasphere interior (hiss) and vicinity (EMIC, chorus) help control the acceleration and loss of radiation belt particles. Thus, understanding the extent, structure, content, and dynamics of the plasmasphere is crucial to understanding radiation belt losses. The Van Allen Probes mission uses two methods to determine the total plasma density. First, the upper hybrid resonance ( ...

Jahn, J.-M.; Goldstein, J.; Kurth, W.S.; Thaller, S.; De Pascuale, S.; Wygant, J.; Reeves, G.D.; Spence, H.E.;

YEAR: 2020     DOI: 10.1029/2019JA026860

cold plasma density; plasmasphere; spacecraft charging; Van Allen Probes; wave resonances

Observations and measurement techniques

There have now been over 50 years of in situ measurements of the ring current. As the measurement capabilities have increased, and more missions have contributed, a remarkably consistent picture has developed of the characteristics of the ring current. In this paper, we review the observations of the ring current, starting from the satellites in the early 60’s, the breakthrough of Explorer 45 identifying the particle population that creates the ring current, and the surprises when the first composition measurements at low ...

Kistler, Lynn;

YEAR: 2020     DOI: 10.1016/B978-0-12-815571-4.00010-X

ring current; instrumentation; Van Allen Probes

2019

Rapid Precipitation of Relativistic Electron by EMIC Rising-Tone Emissions Observed by the Van Allen Probes

On 23 February 2014, Van Allen Probes sensors observed quite strong electromagnetic ion cyclotron (EMIC) waves in the outer dayside magnetosphere. The maximum amplitude was more than 14 nT, comparable to 7\% of the magnitude of the ambient magnetic field. The EMIC waves consisted of a series of coherent rising tone emissions. Rising tones are excited sporadically by energetic protons. At the same time, the probes detected drastic fluctuations in fluxes of MeV electrons. It was found that the electron fluxes decreased by more ...

Nakamura, S.; Omura, Y.; Kletzing, C.; Baker, D.;

YEAR: 2019     DOI: 10.1029/2019JA026772

EMIC waves; Magnetosphere; microburst; nonlinear; Radiation belt; Van Allen Probes; Wave-particle interaction

Global Survey and Empirical Model of Fast Magnetosonic Waves Over Their Full Frequency Range in Earth\textquoterights Inner Magnetosphere

We investigate the global distribution and provide empirical models of fast magnetosonic waves using the combined observations by the magnetometer and waveform receiver on board Van Allen Probes. The magnetometer measurements of magnetosonic waves indicate a significant wave power within the frequency range from the helium gyrofrequency to 20 Hz at L >= 4 in the afternoon sector, both inside and outside the plasmapause. The waveform receiver measurements indicate a significant wave power from 20 Hz to the lower hybrid resona ...

Ma, Q.; Li, W.; Bortnik, J.; Kletzing, C.; Kurth, W.; Hospodarsky, G.; Wygant, J.;

YEAR: 2019     DOI: 10.1029/2019JA027407

Empirical Fitting; Global Survey; magnetosonic waves; Van Allen Probes; Van Allen Probes observation

Multiharmonic Toroidal Standing Alfv\ en Waves in the Midnight Sector Observed During a Geomagnetically Quiet Period

Excitation of toroidal mode standing Alfv\ en waves in the midnight sector of the inner magnetosphere in association with substorms is well documented, but studies are sparse on dayside sources for the waves. This paper reports observation of midnight toroidal waves by the Van Allen Probe B spacecraft during a geomagnetically quiet period on 12\textemdash13 May 2013. The spacecraft detected toroidal waves excited at odd harmonics below 30 mHz as it moved within the plasmasphere from ~2100 magnetic local time (MLT) to ~0030 M ...

Takahashi, Kazue; Vellante, Massimo; Del Corpo, Alfredo; Claudepierre, Seth; Kletzing, Craig; Wygant, John; Koga, Kiyokazu;

YEAR: 2019     DOI: 10.1029/2019JA027370

Ion foreshock; Nightside magnetosphere; Toroidal Alfven waves; Van Allen Probe; Van Allen Probes

Direct Observation of Subrelativistic Electron Precipitation Potentially Driven by EMIC Waves

Electromagnetic ion cyclotron (EMIC) waves are known to typically cause electron losses into Earth\textquoterights upper atmosphere at >~1 MeV, while the minimum energy of electrons subject to efficient EMIC-driven precipitation loss is unresolved. This letter reports electron precipitation from subrelativistic energies of ~250 keV up to ~1 MeV observed by the Focused Investigations of Relativistic Electron Burst Intensity, Range and Dynamics (FIREBIRD-II) CubeSats, while two Polar Operational Environmental Satellites (POES) ...

Capannolo, L.; Li, W.; Ma, Q.; Chen, L.; Shen, X.-C.; Spence, H.; Sample, J.; Johnson, A.; Shumko, M.; Klumpar, D.; Redmon, R.;

YEAR: 2019     DOI: 10.1029/2019GL084202

electron precipitation; EMIC waves; FIREBIRD-II; quasi linear theory; Radiation belts; Van Allen Probes; wave particle interactions

Eastward Propagating Second Harmonic Poloidal Waves Triggered by Temporary Outward Gradient of Proton Phase Space Density: Van Allen Probe A Observation

Two wave packets of second harmonic poloidal Pc 4 waves with a wave frequency of ~7 mHz were detected by Van Allen Probe A at a radial distance of ~5.8 RE and magnetic local time of 13 hr near the magnetic equator, where plasmaspheric refilling was in progress. Proton butterfly distributions with energy dispersions were also measured at the same time; the proton fluxes at 10-30 keV oscillated with the same frequency as the Pc 4 waves. Using the ion sounding technique, we find that the Pc 4 waves propagated eastward with an a ...

Yamamoto, K.; e, Nos\; Keika, K.; Hartley, D.P.; Smith, C.W.; MacDowall, R.J.; Lanzerotti, L.J.; Mitchell, D.G.; Spence, H.E.; Reeves, G.D.; Wygant, J.R.; Bonnell, J.W.; Oimatsu, S.;

YEAR: 2019     DOI: 10.1029/2019JA027158

drift-bounce resonance; Geomagnetic storm; plasmasphere; ring current; substorm; ULF wave; Van Allen Probes

Effects of a Realistic O + Source on Modeling the Ring Current

We use the UNH-IMEF electric field model to simulate the convection of O+ from the near-earth plasma sheet into the ring current during the March 17, 2015 storm. Using Van Allen Probes data from the night side apogee, we reconstruct a realistic O+ source. Modeling this storm using the UNH-IMEF electric field and a dipole magnetic field has previously been found to have good agreement. Using the realistic source along with drift times and charge exchange loss from these results, we model an inbound pass near the peak of the s ...

Menz, A.M.; Kistler, L.M.; Mouikis, C.G.; Spence, H.E.; Henderson, M.G.;

YEAR: 2019     DOI: 10.1029/2019JA026859

Van Allen Probes

Identifying STEVE\textquoterights Magnetospheric Driver Using Conjugate Observations in the Magnetosphere and on the Ground

The magnetospheric driver of strong thermal emission velocity enhancement (STEVE) is investigated using conjugate observations when Van Allen Probes\textquoteright footprint directly crossed both STEVE and stable red aurora (SAR) arc. In the ionosphere, STEVE is associated with subauroral ion drift features, including electron temperature peak, density gradient, and westward ion flow. The SAR arc at lower latitudes corresponds to regions inside the plasmapause with isotropic plasma heating, which causes redline-only SAR emis ...

Chu, Xiangning; Malaspina, David; Gallardo-Lacourt, Bea; Liang, Jun; Andersson, Laila; Ma, Qianli; Artemyev, Anton; Liu, Jiang; Ergun, Robert; Thaller, Scott; Akbari, Hassanali; Zhao, Hong; Larsen, Brian; Reeves, Geoffrey; Wygant, John; Breneman, Aaron; Tian, Sheng; Connors, Martin; Donovan, Eric; Archer, William; MacDonald, Elizabeth;

YEAR: 2019     DOI: 10.1029/2019GL082789

aurora; kinetic Alfven wave; Plasmapause; STEVE; subauroral ion drift; table red auroral arc; Van Allen Probes

Remote Detection of Drift Resonance Between Energetic Electrons and Ultralow Frequency Waves: Multisatellite Coordinated Observation by Arase and Van Allen Probes

We report the electron flux modulations without corresponding magnetic fluctuations from unique multipoint satellite observations of the Arase (Exploration of Energization and Radiation in Geospace) and the Van Allen Probe (Radiation Belt Storm Probe [RBSP])-B satellites. On 30 March 2017, both Arase and RBSP-B observed periodic fluctuations in the relativistic electron flux with energies ranging from 500 keV to 2 MeV when they were located near the magnetic equator in the morning and dusk local time sectors, respectively. A ...

Teramoto, M.; Hori, T.; Saito, S.; Miyoshi, Y.; Kurita, S.; Higashio, N.; Matsuoka, A.; Kasahara, Y.; Kasaba, Y.; Takashima, T.; Nomura, R.; e, Nos\; Fujimoto, A.; Tanaka, Y.-M.; Shoji, M.; Tsugawa, Y.; Shinohara, M.; Shinohara, I.; Blake, J.; Fennell, J.F.; Claudepierre, S.G.; Turner, D.; Kletzing, C.; Sormakov, D.; Troshichev, O.;

YEAR: 2019     DOI: 10.1029/2019GL084379

Van Allen Probes

The Storm-Time Ring Current Response to ICMEs and CIRs Using Van Allen Probe Observations

Using Van Allen Probe observations of the inner magnetosphere during geomagnetic storms driven by interplanetary coronal mass ejections (ICMEs) and corotating interaction regions (CIRs), we characterize the impact of these drivers on the storm-time ring current development. Using 25 ICME- and 35 CIR-driven storms, we have determined the ring current pressure development during the prestorm, main, early-recovery, and late-recovery storm phases, as a function of magnetic local time, L shell and ion species (H+, He+, and O+) ov ...

Mouikis, C.; Bingham, S.; Kistler, L.; Farrugia, C.; Spence, H.; Reeves, G.; Gkioulidou, M.; Mitchell, D.; Kletzing, C.;

YEAR: 2019     DOI: 10.1029/2019JA026695

ICME vs CI; R Ion composition; Ring Current Pressure; Storm phases; Van Allen Probes

The Storm-Time Ring Current Response to ICMEs and CIRs Using Van Allen Probe Observations

Using Van Allen Probe observations of the inner magnetosphere during geomagnetic storms driven by interplanetary coronal mass ejections (ICMEs) and corotating interaction regions (CIRs), we characterize the impact of these drivers on the storm-time ring current development. Using 25 ICME- and 35 CIR-driven storms, we have determined the ring current pressure development during the prestorm, main, early-recovery, and late-recovery storm phases, as a function of magnetic local time, L shell and ion species (H+, He+, and O+) ov ...

Mouikis, C.; Bingham, S.; Kistler, L.; Farrugia, C.; Spence, H.; Reeves, G.; Gkioulidou, M.; Mitchell, D.; Kletzing, C.;

YEAR: 2019     DOI: 10.1029/2019JA026695

ICME vs CI; R Ion composition; Ring Current Pressure; Storm phases; Van Allen Probes

Variability of Quasilinear Diffusion Coefficients for Plasmaspheric Hiss

In the outer radiation belt, the acceleration and loss of high-energy electrons is largely controlled by wave-particle interactions. Quasilinear diffusion coefficients are an efficient way to capture the small-scale physics of wave-particle interactions due to magnetospheric wave modes such as plasmaspheric hiss. The strength of quasilinear diffusion coefficients as a function of energy and pitch angle depends on both wave parameters and plasma parameters such as ambient magnetic field strength, plasma number density, and co ...

Watt, C.; Allison, H.; Meredith, N.; Thompson, R.; Bentley, S.; Rae, I.; Glauert, S.; Horne, R.;

YEAR: 2019     DOI: 10.1029/2018JA026401

empirical; Magnetosphere; parameterization; stochastic; Van Allen Probes; wave-particle interactions

Efficacy of Electric Field Models in Reproducing Observed Ring Current Ion Spectra During Two Geomagnetic Storms

We use the UNH-IMEF, Weimer 1996, https://doi.org/10.1029/96GL02255 and Volland-Stern electric field models along with a dipole magnetic field to calculate drift paths for particles that reach the Van Allen Probes\textquoteright orbit for two inbound passes during two large geomagnetic storms. We compare the particle access in the models with the observed particle access using both realistic and enhanced solar wind model parameters. To test the accuracy of the drift paths, we estimate the H+ charge exchange loss along these ...

Menz, A.M.; Kistler, L.M.; Mouikis, C.G.; Matsui, H.; Spence, H.E.; Thaller, S.A.; Wygant, J.R.;

YEAR: 2019     DOI: 10.1029/2019JA026683

Van Allen Probes

Efficacy of Electric Field Models in Reproducing Observed Ring Current Ion Spectra During Two Geomagnetic Storms

We use the UNH-IMEF, Weimer 1996, https://doi.org/10.1029/96GL02255 and Volland-Stern electric field models along with a dipole magnetic field to calculate drift paths for particles that reach the Van Allen Probes\textquoteright orbit for two inbound passes during two large geomagnetic storms. We compare the particle access in the models with the observed particle access using both realistic and enhanced solar wind model parameters. To test the accuracy of the drift paths, we estimate the H+ charge exchange loss along these ...

Menz, A.M.; Kistler, L.M.; Mouikis, C.G.; Matsui, H.; Spence, H.E.; Thaller, S.A.; Wygant, J.R.;

YEAR: 2019     DOI: 10.1029/2019JA026683

Van Allen Probes

Lightning Contribution to Overall Whistler Mode Wave Intensities in the Plasmasphere

Electromagnetic waves generated by lightning propagate into the plasmasphere as dispersed whistlers. They can therefore influence the overall wave intensity in space, which, in turn, is important for dynamics of the Van Allen radiation belts. We analyze spacecraft measurements in low-Earth orbit as well as in high-altitude equatorial region, together with a ground-based estimate of lightning activity. We accumulate wave intensities when the spacecraft are magnetically connected to thunderstorms and compare them with measurem ...

ahlava, J.; emec, F.; Santolik, O.; a, Kolma\v; Hospodarsky, G.; Parrot, M.; Kurth, W.; Kletzing, C.;

YEAR: 2019     DOI: 10.1029/2019GL083918

DEMETER; Lightning; Van Allen Probes; whistler mode; WWLLN



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