Bibliography



Found 114 entries in the Bibliography.


Showing entries from 1 through 50


2021

Investigation of small-scale electron density irregularities observed by the Arase and Van Allen Probes satellites inside and outside the plasmasphere

AbstractIn-situ electron density profiles obtained from Arase in the night magnetic local time (MLT) sector and from RBSP-B covering all MLTs are used to study the small-scale density irregularities present in the plasmasphere and near the plasmapause. Electron density perturbations with amplitudes > 10\% from background density and with time-scales less than 30-min are investigated here as the small-scale density irregularities. The statistical survey of the density irregularities is carried out using nearly two years of de ...

Thomas, Neethal; Shiokawa, Kazuo; Miyoshi, Yoshizumi; Kasahara, Yoshiya; Shinohara, Iku; Kumamoto, Atsushi; Tsuchiya, Fuminori; Matsuoka, Ayako; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomo; Asamura, Kazushi; Wang, Shiang-Yu; Kazama, Yoichi; Tam, Sunny; Chang, Tzu-Fang; Wang, Bo-Jhou; Wygant, John; Breneman, Aaron; Reeves, Geoff;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA027917

Electron density; small-scale density irregularities; plasmasphere; inner magnetosphere; Van Allen Probes; Arase

Investigation of small-scale electron density irregularities observed by the Arase and Van Allen Probes satellites inside and outside the plasmasphere

AbstractIn-situ electron density profiles obtained from Arase in the night magnetic local time (MLT) sector and from RBSP-B covering all MLTs are used to study the small-scale density irregularities present in the plasmasphere and near the plasmapause. Electron density perturbations with amplitudes > 10\% from background density and with time-scales less than 30-min are investigated here as the small-scale density irregularities. The statistical survey of the density irregularities is carried out using nearly two years of de ...

Thomas, Neethal; Shiokawa, Kazuo; Miyoshi, Yoshizumi; Kasahara, Yoshiya; Shinohara, Iku; Kumamoto, Atsushi; Tsuchiya, Fuminori; Matsuoka, Ayako; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomo; Asamura, Kazushi; Wang, Shiang-Yu; Kazama, Yoichi; Tam, Sunny; Chang, Tzu-Fang; Wang, Bo-Jhou; Wygant, John; Breneman, Aaron; Reeves, Geoff;

YEAR: 2021     DOI: https://doi.org/10.1029/2020JA027917

Electron density; small-scale density irregularities; plasmasphere; inner magnetosphere; Van Allen Probes; Arase

2020

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

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

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

Statistical Evidence for EMIC Wave Excitation Driven by Substorm Injection and Enhanced Solar Wind Pressure in the Earth s Magnetosphere: Two Different EMIC Wave Sources

Substorm injection and solar wind dynamic pressure have long been considered as two main drivers of electromagnetic ion cyclotron (EMIC) wave excitation, but clear observational evidence is still lacking. With Van Allen Probes data from 2012–2017, we have investigated the roles of the two EMIC wave drivers separately, by using time-modified AE+ and . Both the occurrence rate and magnetic amplitude of waves significantly increase with the enhancement of each index. During large AE+, EMIC waves are mainly generated in the du ...

Chen, Huayue; Gao, Xinliang; Lu, Quanming; Tsurutani, Bruce; Wang, Shui;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL090275

EMIC wave; wave excitation; source region; substorm injection; solar wind dynamic pressure; Earth s magnetosphere; Van Allen Probes

Suprathermal Electron Evolution Under the Competition Between Plasmaspheric Plume Hiss Wave Heating and Collisional Cooling

Suprathermal electrons are a major heat source of ionospheric plasma. How the suprathermal electrons evolve during their bounces inside the plasmasphere is a fundamental question for the magnetosphere-ionosphere coupling. On the basis of Van Allen Probes observations and quasi-linear simulations, we present here the first quantitative study on the evolution of suprathermal electrons under the competition between Landau heating by whistler mode hiss waves and Coulomb collisional cooling by background plasma inside a plasmasph ...

Wang, Zhongshan; Su, Zhenpeng; Liu, Nigang; Dai, Guyue; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL089649

magnetosphere-ionosphere coupling; whistler mode hiss waves; Landau resonance; Coulomb collisions; suprathermal electrons; ring current; Van Allen Probes

Lower-Band “Monochromatic” Chorus Riser Subelement/Wave Packet Observations

Three lower-band (f < 0.5 fce) chorus riser elements detected in the dayside generation region were studied in detail using the Van Allen Probe data. Two subelements/wave packets within each riser were examined for their wave “frequency” constancy within seven consecutive wave cycles. The seven wave cycles contained the maximum amplitudes of the subelements/packets. Maximum variance B1 zero crossings were used for the identification of wave cycle start and stop times. It is found that the frequency is constant to with ...

Tsurutani, Bruce; Chen, Rui; Gao, Xinliang; Lu, Quanming; Pickett, Jolene; Lakhina, Gurbax; Sen, Abhijit; Hajra, Rajkumar; Park, Sang; Falkowski, Barbara;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028090

chorus coherency; chorus subelement monochromaticity; a modified theory needed; 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

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

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

Can Solar Wind Decompressive Discontinuities Suppress Magnetospheric Electromagnetic Ion Cyclotron Waves Associated With Fresh Proton Injections?

Electromagnetic ion cyclotron (EMIC) waves play an important role in the energy transfer among particles of different energies and species in the magnetosphere, whose drivers have been commonly recognized as solar wind compressions and storm/substorm proton injections. However, how the solar wind decompressions related to frequently occurring discontinuities compete with the proton injections in the evolution of EMIC waves has been rarely investigated. Here we present a complete end-to-end observation by Wind, THEMIS, and Va ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2020     DOI: https://doi.org/10.1029/2020GL090296

EMIC waves; solar wind discontinuity; storm/substorm injection; wave generation; adiabatic deceleration; inner magnetosphere; Van Allen Probes

A Short-lived Three-Belt Structure for sub-MeV Electrons in the Van Allen Belts: Time Scale and Energy Dependence

In this study we focus on the radiation belt dynamics driven by the geomagnetic storms during September 2017. Besides the long-lasting three-belt structures of ultrarelativistic electrons (>2 MeV, existing for tens of days), which has been studied intensively during the Van Allen Probe era, it is found that magnetospheric electrons of hundreds of keVs can also have three-belt structures at similar L extent during storm time. Measurements of 500–800 keV electrons from MagEIS instrument onboard Van Allen Probes show double- ...

Hao, Y.; Zong, Q.-G.; Zhou, X.-Z.; Zou, H.; Rankin, R.; Sun, Y.; Chen, X.; Liu, Y.; . Y. Fu, S; Baker, D.; Spence, H.; Blake, J.; Reeves, G.; Claudepierre, S.;

YEAR: 2020     DOI: https://doi.org/10.1029/2020JA028031

storage ring; three-belt structure; hiss wave; electron lifetime; Radial Transport; 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

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electron instabi ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

plasmasphere; Plasmaspheric Hiss; Radiation belt; Van Allen Probes; Wave Dissipation; wave generation; wave propagation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electron instabi ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

plasmasphere; Plasmaspheric Hiss; Radiation belt; Van Allen Probes; Wave Dissipation; wave generation; wave propagation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electron instabi ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

plasmasphere; Plasmaspheric Hiss; Radiation belt; Van Allen Probes; Wave Dissipation; wave generation; wave propagation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electron instabi ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

plasmasphere; Plasmaspheric Hiss; Radiation belt; Van Allen Probes; Wave Dissipation; wave generation; wave propagation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Abstract Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electro ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

Plasmaspheric Hiss; Radiation belt; plasmasphere; wave generation; wave propagation; Wave Dissipation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Abstract Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electro ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

Plasmaspheric Hiss; Radiation belt; plasmasphere; wave generation; wave propagation; Wave Dissipation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Abstract Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electro ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

Plasmaspheric Hiss; Radiation belt; plasmasphere; wave generation; wave propagation; Wave Dissipation

Comprehensive Observations of Substorm-Enhanced Plasmaspheric Hiss Generation, Propagation, and Dissipation

Abstract Plasmaspheric hiss is an important whistler-mode emission shaping the Van Allen radiation belt environment. How the plasmaspheric hiss waves are generated, propagate, and dissipate remains under intense debate. With the five spacecraft of Van Allen Probes, Exploration of energization and Radiation in Geospace (Arase), and Geostationary Operational Environmental Satellites missions at widely spaced locations, we present here the first comprehensive observations of hiss waves growing from the substorm-injected electro ...

Liu, Nigang; Su, Zhenpeng; Gao, Zhonglei; Zheng, Huinan; Wang, Yuming; Wang, Shui; Miyoshi, Yoshizumi; Shinohara, Iku; Kasahara, Yoshiya; Tsuchiya, Fuminori; Kumamoto, Atsushi; Matsuda, Shoya; Shoji, Masafumi; Mitani, Takefumi; Takashima, Takeshi; Kazama, Yoichi; Wang, Bo-Jhou; Wang, Shiang-Yu; Jun, Chae-Woo; Chang, Tzu-Fang; W. Y. Tam, Sunny; Kasahara, Satoshi; Yokota, Shoichiro; Keika, Kunihiro; Hori, Tomoaki; Matsuoka, Ayako;

YEAR: 2020     DOI: 10.1029/2019GL086040

Plasmaspheric Hiss; Radiation belt; plasmasphere; wave generation; wave propagation; Wave Dissipation

2019

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

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

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

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

Quenching of Equatorial Magnetosonic Waves by Substorm Proton Injections

Near equatorial (fast) magnetosonic waves, characterized by high magnetic compressibility, are whistler-mode emissions destabilized by proton shell/ring distributions. In the past, substorm proton injections are widely known to intensify magnetosonic waves in the inner magnetosphere. Here we report the unexpected observations by the Van Allen Probes of the magnetosonic wave quenching associated with the substorm proton injections under both high- and low-density conditions. The enhanced proton thermal pressure distorted the ...

Dai, Guyue; Su, Zhenpeng; Liu, Nigang; Wang, Bin; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2019     DOI: 10.1029/2019GL082944

Bernstein mode instability; magnetosonic wave; Radiation belt; ring current; substorm injection; Van Allen Probes; Wave-particle interaction

Statistical Properties of Hiss in Plasmaspheric Plumes and Associated Scattering Losses of Radiation Belt Electrons

Whistler mode hiss acts as an important loss mechanism contributing to the radiation belt electron dynamics inside the plasmasphere and plasmaspheric plumes. Based on Van Allen Probes observations from September 2012 to December 2015, we conduct a detailed analysis of hiss properties in plasmaspheric plumes and illustrate that corresponding to the highest occurrence probability of plumes at L = 5.0\textendash6.0 and MLT = 18\textendash21, hiss emissions occur concurrently with a rate of >~80\%. Plume hiss can efficiently sca ...

Zhang, Wenxun; Ni, Binbin; Huang, He; Summers, Danny; Fu, Song; Xiang, Zheng; Gu, Xudong; Cao, Xing; Lou, Yuequn; Hua, Man;

YEAR: 2019     DOI: 10.1029/2018GL081863

Electron scattering; plasmaspheric plumes; plume hiss; Van Allen Probes

EMIC waves converted from equatorial noise due to M/Q=2 ions in the plasmasphere: Observations from Van Allen Probes and Arase

Equatorial noise (EN) emissions are observed inside and outside the plasmapause. EN emissions are referred to as magnetosonic mode waves. Using data from Van Allen Probes and Arase, we found conversion from EN emissions to electromagnetic ion cyclotron (EMIC) waves in the plasmasphere and in the topside ionosphere. A low frequency part of EN emissions becomes EMIC waves through branch splitting of EN emissions, and the mode conversion from EN to EMIC waves occurs around the frequency of M/Q=2 (deuteron and/or alpha particles ...

Miyoshi, Y.; Matsuda, S.; Kurita, S.; Nomura, K.; Keika, K.; Shoji, M.; Kitamura, N.; Kasahara, Y.; Matsuoka, A.; Shinohara, I.; Shiokawa, K.; Machida, S.; Santolik, O.; Boardsen, S.A.; Horne, R.B.; Wygant, J.F.;

YEAR: 2019     DOI: 10.1029/2019GL083024

Arase; EMIC; M/Q=2 ions; Magnetsonic waves; plasmasphere; Van Allen Probes

EMIC waves converted from equatorial noise due to M/Q=2 ions in the plasmasphere: Observations from Van Allen Probes and Arase

Equatorial noise (EN) emissions are observed inside and outside the plasmapause. EN emissions are referred to as magnetosonic mode waves. Using data from Van Allen Probes and Arase, we found conversion from EN emissions to electromagnetic ion cyclotron (EMIC) waves in the plasmasphere and in the topside ionosphere. A low frequency part of EN emissions becomes EMIC waves through branch splitting of EN emissions, and the mode conversion from EN to EMIC waves occurs around the frequency of M/Q=2 (deuteron and/or alpha particles ...

Miyoshi, Y.; Matsuda, S.; Kurita, S.; Nomura, K.; Keika, K.; Shoji, M.; Kitamura, N.; Kasahara, Y.; Matsuoka, A.; Shinohara, I.; Shiokawa, K.; Machida, S.; Santolik, O.; Boardsen, S.A.; Horne, R.B.; Wygant, J.F.;

YEAR: 2019     DOI: 10.1029/2019GL083024

Arase; EMIC; M/Q=2 ions; Magnetsonic waves; plasmasphere; Van Allen Probes

Sensitivity of EMIC Wave-Driven Scattering Loss of Ring Current Protons to Wave Normal Angle Distribution

Electromagnetic ion cyclotron waves have long been recognized to play a crucial role in the dynamic loss of ring current protons. While the field-aligned propagation approximation of electromagnetic ion cyclotron waves was widely used to quantify the scattering loss of ring current protons, in this study, we find that the wave normal distribution strongly affects the pitch angle scattering efficiency of protons. Increase of peak normal angle or angular width can considerably reduce the scattering rates of <=10 keV protons. F ...

Cao, Xing; Ni, Binbin; Summers, Danny; Shprits, Yuri; Gu, Xudong; Fu, Song; Lou, Yuequn; Zhang, Yang; Ma, Xin; Zhang, Wenxun; Huang, He; Yi, Juan;

YEAR: 2019     DOI: 10.1029/2018GL081550

EMIC waves; Quasi-linear diffusion; Ring current protons; Van Allen Probes; wave-particle interactions

2018

Nonlinear coupling between whistler-mode chorus and electron cyclotron harmonic waves in the magnetosphere

Electromagnetic whistler-mode chorus and electrostatic electron cyclotron harmonic (ECH) waves can contribute significantly to auroral electron precipitation and radiation belt electron acceleration. In the past, linear and nonlinear wave-particle interactions have been proposed to explain the occurrences of these magnetospheric waves. By analyzing Van Allen Probes data, we present here the first evidence for nonlinear coupling between chorus and ECH waves. The sum-frequency and difference-frequency interactions produced the ...

Gao, Zhonglei; Su, Zhenpeng; Xiao, Fuliang; Summers, Danny; Liu, Nigang; Zheng, Huinan; Wang, Yuming; Wei, Fengsi; Wang, Shui;

YEAR: 2018     DOI: 10.1029/2018GL080635

aurora; Chorus wave; electron cyclotron harmonic wave; nonlinear wave-wave interaction; Radiation belt; Van Allen Probes

Nonlinear coupling between whistler-mode chorus and electron cyclotron harmonic waves in the magnetosphere

Electromagnetic whistler-mode chorus and electrostatic electron cyclotron harmonic (ECH) waves can contribute significantly to auroral electron precipitation and radiation belt electron acceleration. In the past, linear and nonlinear wave-particle interactions have been proposed to explain the occurrences of these magnetospheric waves. By analyzing Van Allen Probes data, we present here the first evidence for nonlinear coupling between chorus and ECH waves. The sum-frequency and difference-frequency interactions produced the ...

Gao, Zhonglei; Su, Zhenpeng; Xiao, Fuliang; Summers, Danny; Liu, Nigang; Zheng, Huinan; Wang, Yuming; Wei, Fengsi; Wang, Shui;

YEAR: 2018     DOI: 10.1029/2018GL080635

aurora; Chorus wave; electron cyclotron harmonic wave; nonlinear wave-wave interaction; Radiation belt; Van Allen Probes

Rapid loss of relativistic electrons by EMIC waves in the outer radiation belt observed by Arase, Van Allen Probes, and the PWING ground stations

There has been increasing evidence for pitch angle scattering of relativistic electrons by electromagnetic ion cyclotron (EMIC) waves. Theoretical studies have predicted that the loss time scale of MeV electrons by EMIC waves can be very fast, suggesting that MeV electron fluxes rapidly decrease in association with the EMIC wave activity. This study reports on a unique event of MeV electron loss induced by EMIC waves based on Arase, Van Allen Probes, and ground-based network observations. Arase observed a signature of MeV el ...

Kurita, S.; Miyoshi, Y.; Shiokawa, K.; Higashio, N.; Mitani, T.; Takashima, T.; Matsuoka, A.; Shinohara, I.; Kletzing, C.; Blake, J.; Claudepierre, S.; Connors, M.; Oyama, S.; Nagatsuma, T.; Sakaguchi, K.; Baishev, D.; Otsuka, Y.;

YEAR: 2018     DOI: 10.1029/2018GL080262

EMIC waves; loss; PWING project; Radiation belt; The Arase satellite; Van Allen Probes

Rapid loss of relativistic electrons by EMIC waves in the outer radiation belt observed by Arase, Van Allen Probes, and the PWING ground stations

There has been increasing evidence for pitch angle scattering of relativistic electrons by electromagnetic ion cyclotron (EMIC) waves. Theoretical studies have predicted that the loss time scale of MeV electrons by EMIC waves can be very fast, suggesting that MeV electron fluxes rapidly decrease in association with the EMIC wave activity. This study reports on a unique event of MeV electron loss induced by EMIC waves based on Arase, Van Allen Probes, and ground-based network observations. Arase observed a signature of MeV el ...

Kurita, S.; Miyoshi, Y.; Shiokawa, K.; Higashio, N.; Mitani, T.; Takashima, T.; Matsuoka, A.; Shinohara, I.; Kletzing, C.; Blake, J.; Claudepierre, S.; Connors, M.; Oyama, S.; Nagatsuma, T.; Sakaguchi, K.; Baishev, D.; Otsuka, Y.;

YEAR: 2018     DOI: 10.1029/2018GL080262

EMIC waves; loss; PWING project; Radiation belt; The Arase satellite; Van Allen Probes

Rapid loss of relativistic electrons by EMIC waves in the outer radiation belt observed by Arase, Van Allen Probes, and the PWING ground stations

There has been increasing evidence for pitch angle scattering of relativistic electrons by electromagnetic ion cyclotron (EMIC) waves. Theoretical studies have predicted that the loss time scale of MeV electrons by EMIC waves can be very fast, suggesting that MeV electron fluxes rapidly decrease in association with the EMIC wave activity. This study reports on a unique event of MeV electron loss induced by EMIC waves based on Arase, Van Allen Probes, and ground-based network observations. Arase observed a signature of MeV el ...

Kurita, S.; Miyoshi, Y.; Shiokawa, K.; Higashio, N.; Mitani, T.; Takashima, T.; Matsuoka, A.; Shinohara, I.; Kletzing, C.; Blake, J.; Claudepierre, S.; Connors, M.; Oyama, S.; Nagatsuma, T.; Sakaguchi, K.; Baishev, D.; Otsuka, Y.;

YEAR: 2018     DOI: 10.1029/2018GL080262

EMIC waves; loss; PWING project; Radiation belt; The Arase satellite; Van Allen Probes

Fine structure of whistler-mode hiss in plasmaspheric plumes observed by the Van Allen Probes

We survey 3 years (2013-2015) of data from the Van Allen Probes related to plasmaspheric plume crossing events. We detect 194 plume crossing events, and we find that 97\% of the plumes are accompanied by VLF hiss emissions. The plumes are mainly detected on the duskside or dayside. Careful examination of the hiss spectra reveals that all hiss emissions consist of obvious fine structure. Application of a band pass filter reveals that the fine structure is consistent with the occurrence of discrete wave packets. The hiss data ...

Nakamura, S.; Omura, Y.; Summers, D.;

YEAR: 2018     DOI: 10.1029/2018JA025803

fine structure; hiss; nonlinear; plasmaspheric plume; Van Allen Probes

Longitudinal Structure of Oxygen Torus in the Inner Magnetosphere: Simultaneous Observations by Arase and Van Allen Probe A

Simultaneous observations of the magnetic field and plasma waves made by the Arase and Van Allen Probe A satellites at different magnetic local time (MLT) enable us to deduce the longitudinal structure of an oxygen torus for the first time. During 04:00\textendash07:10 UT on 24 April 2017, Arase flew from L = 6.2 to 2.0 in the morning sector and detected an enhancement of the average plasma mass up to ~3.5 amu around L = 4.9\textendash5.2 and MLT = 5.0 hr, implying that the plasma consists of approximately 15\% O+ ions. Prob ...

e, M.; Matsuoka, A.; Kumamoto, A.; Kasahara, Y.; Goldstein, J.; Teramoto, M.; Tsuchiya, F.; Matsuda, S.; Shoji, M.; Imajo, S.; Oimatsu, S.; Yamamoto, K.; Obana, Y.; Nomura, R.; Fujimoto, A.; Shinohara, I.; Miyoshi, Y.; Kurth, W.; Kletzing, C.; Smith, C.; MacDowall, R.;

YEAR: 2018     DOI: 10.1029/2018GL080122

Arase satellite; Geomagnetic storm; inner magnetosphere; oxygen torus; simultaneous observation; Van Allen Probes; Van Allen Probes satellite

Longitudinal Structure of Oxygen Torus in the Inner Magnetosphere: Simultaneous Observations by Arase and Van Allen Probe A

Simultaneous observations of the magnetic field and plasma waves made by the Arase and Van Allen Probe A satellites at different magnetic local time (MLT) enable us to deduce the longitudinal structure of an oxygen torus for the first time. During 04:00\textendash07:10 UT on 24 April 2017, Arase flew from L = 6.2 to 2.0 in the morning sector and detected an enhancement of the average plasma mass up to ~3.5 amu around L = 4.9\textendash5.2 and MLT = 5.0 hr, implying that the plasma consists of approximately 15\% O+ ions. Prob ...

e, M.; Matsuoka, A.; Kumamoto, A.; Kasahara, Y.; Goldstein, J.; Teramoto, M.; Tsuchiya, F.; Matsuda, S.; Shoji, M.; Imajo, S.; Oimatsu, S.; Yamamoto, K.; Obana, Y.; Nomura, R.; Fujimoto, A.; Shinohara, I.; Miyoshi, Y.; Kurth, W.; Kletzing, C.; Smith, C.; MacDowall, R.;

YEAR: 2018     DOI: 10.1029/2018GL080122

Arase satellite; Geomagnetic storm; inner magnetosphere; oxygen torus; simultaneous observation; Van Allen Probes; Van Allen Probes satellite

Longitudinal Structure of Oxygen Torus in the Inner Magnetosphere: Simultaneous Observations by Arase and Van Allen Probe A

Simultaneous observations of the magnetic field and plasma waves made by the Arase and Van Allen Probe A satellites at different magnetic local time (MLT) enable us to deduce the longitudinal structure of an oxygen torus for the first time. During 04:00\textendash07:10 UT on 24 April 2017, Arase flew from L = 6.2 to 2.0 in the morning sector and detected an enhancement of the average plasma mass up to ~3.5 amu around L = 4.9\textendash5.2 and MLT = 5.0 hr, implying that the plasma consists of approximately 15\% O+ ions. Prob ...

e, M.; Matsuoka, A.; Kumamoto, A.; Kasahara, Y.; Goldstein, J.; Teramoto, M.; Tsuchiya, F.; Matsuda, S.; Shoji, M.; Imajo, S.; Oimatsu, S.; Yamamoto, K.; Obana, Y.; Nomura, R.; Fujimoto, A.; Shinohara, I.; Miyoshi, Y.; Kurth, W.; Kletzing, C.; Smith, C.; MacDowall, R.;

YEAR: 2018     DOI: 10.1029/2018GL080122

Arase satellite; Geomagnetic storm; inner magnetosphere; oxygen torus; simultaneous observation; Van Allen Probes; Van Allen Probes satellite

Longitudinal Structure of Oxygen Torus in the Inner Magnetosphere: Simultaneous Observations by Arase and Van Allen Probe A

Simultaneous observations of the magnetic field and plasma waves made by the Arase and Van Allen Probe A satellites at different magnetic local time (MLT) enable us to deduce the longitudinal structure of an oxygen torus for the first time. During 04:00\textendash07:10 UT on 24 April 2017, Arase flew from L = 6.2 to 2.0 in the morning sector and detected an enhancement of the average plasma mass up to ~3.5 amu around L = 4.9\textendash5.2 and MLT = 5.0 hr, implying that the plasma consists of approximately 15\% O+ ions. Prob ...

e, M.; Matsuoka, A.; Kumamoto, A.; Kasahara, Y.; Goldstein, J.; Teramoto, M.; Tsuchiya, F.; Matsuda, S.; Shoji, M.; Imajo, S.; Oimatsu, S.; Yamamoto, K.; Obana, Y.; Nomura, R.; Fujimoto, A.; Shinohara, I.; Miyoshi, Y.; Kurth, W.; Kletzing, C.; Smith, C.; MacDowall, R.;

YEAR: 2018     DOI: 10.1029/2018GL080122

Arase satellite; Geomagnetic storm; inner magnetosphere; oxygen torus; simultaneous observation; Van Allen Probes; Van Allen Probes satellite

Generation of lower L -shell dayside chorus by energetic electrons from the plasmasheet

Currently, the generation mechanism for the lower L-shell dayside chorus has still remained an open question. Here, we report two storm events: 06-07 March 2016 and 20-21 January 2016, when Van Allen Probes observed enhanced dayside chorus with lower and higher wave normal angles (the angles between the wave vector and the geomagnetic field) in the region of L = 3.5-6.3 and MLT = 5.6-13.5. Hot and energetic (\~ 1-100 keV) electrons displayed enhancements in fluxes and anisotropy when they were injected from the plasmasheet a ...

He, Yihua; Xiao, Fuliang; Su, Zhenpeng; Zheng, Huinan; Yang, Chang; Liu, Si; Zhou, Qinghua;

YEAR: 2018     DOI: 10.1029/2017JA024889

Dayside chorus generation; Radiation belt; Van Allen Probes; Wave-particle interaction

Impulsively Excited Nightside Ultralow Frequency Waves Simultaneously Observed On and Off the Magnetic Equator

The Arase spacecraft is capable of observing ultralow-frequency waves in the inner magnetosphere at intermediate magnetic latitudes, a region sparsely covered by previous space craft missions. We report a series of impulsively excited fundamental toroidal mode standing Alfv\ en waves in the midnight sector observed by Arase outside the plasmasphere at magnetic latitudes 13\textendash24\textdegree . The wave onsets are concurrent with Pi2 onsets detected by the Van Allen Probe B spacecraft at the magnetic equator in the dusks ...

Takahashi, Kazue; Denton, Richard; Motoba, Tetsuo; Matsuoka, Ayako; Kasaba, Yasumasa; Kasahara, Yoshiya; Teramoto, Mariko; Shoji, Masafumi; Takahashi, Naoko; Miyoshi, Yoshizumi; e, Masahito; Kumamoto, Atsushi; Tsuchiya, Fuminori; Redmon, Robert; Rodriguez, Juan;

YEAR: 2018     DOI: 10.1029/2018GL078731

Van Allen Probes

Impulsively Excited Nightside Ultralow Frequency Waves Simultaneously Observed On and Off the Magnetic Equator

The Arase spacecraft is capable of observing ultralow-frequency waves in the inner magnetosphere at intermediate magnetic latitudes, a region sparsely covered by previous space craft missions. We report a series of impulsively excited fundamental toroidal mode standing Alfv\ en waves in the midnight sector observed by Arase outside the plasmasphere at magnetic latitudes 13\textendash24\textdegree . The wave onsets are concurrent with Pi2 onsets detected by the Van Allen Probe B spacecraft at the magnetic equator in the dusks ...

Takahashi, Kazue; Denton, Richard; Motoba, Tetsuo; Matsuoka, Ayako; Kasaba, Yasumasa; Kasahara, Yoshiya; Teramoto, Mariko; Shoji, Masafumi; Takahashi, Naoko; Miyoshi, Yoshizumi; e, Masahito; Kumamoto, Atsushi; Tsuchiya, Fuminori; Redmon, Robert; Rodriguez, Juan;

YEAR: 2018     DOI: 10.1029/2018GL078731

Van Allen Probes

Magnetosonic harmonic falling and rising frequency emissions potentially generated by nonlinear wave-wave interactions in the Van Allen radiation belts

Magnetosonic waves play a potentially important role in the complex evolution of the radiation belt electrons. These waves typically appear as discrete emission lines along the proton gyrofrequency harmonics, consistent with the prediction of the local Bernstein mode instability of hot proton ring distributions. Magnetosonic waves are nearly dispersionless particularly at low harmonics and therefore have the roughly unchanged frequency-time structures during the propagation. On the basis of Van Allen Probes observations, we ...

Liu, Nigang; Su, Zhenpeng; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2018     DOI: 10.1029/2018GL079232

Bernstein mode instability; magnetosonic wave; Radiation belt; ring current; rising/falling frequency; Van Allen Probes; wave propagation

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

Electron Scattering by Plasmaspheric Hiss in a Nightside Plume

Plasmaspheric hiss is known to play an important role in radiation belt electron dynamics in high plasma density regions. We present observations of two crossings of a plasmaspheric plume by the Van Allen Probes on 26 December 2012, which occurred unusually at the post-midnight-to-dawn sector between L ~ 4\textendash6 during a geomagnetically quiet period. This plume exhibited pronounced electron densities higher than those of the average plume level. Moderate hiss emissions accompanied the two plume crossings with the peak ...

Zhang, Wenxun; Fu, Song; Gu, Xudong; Ni, Binbin; Xiang, Zheng; Summers, Danny; Zou, Zhengyang; Cao, Xing; Lou, Yuequn; Hua, Man;

YEAR: 2018     DOI: 10.1029/2018GL077212

Electron scattering; nightside plumes; Plasmaspheric Hiss; Van Allen Probes

Van Allen Probes observations of drift-bounce resonance and energy transfer between energetic ring current protons and poloidal Pc4 wave

A poloidal Pc4 wave and proton flux oscillations are observed in the inner magnetosphere on the dayside near the magnetic equator by the Van Allen Probes spacecraft on 2 March 2014. The flux oscillations are observed in the energy range of 67.0 keV to 268.8 keV with the same frequency of the poloidal Pc4 wave. We find pitch angle and energy dispersion in the phase difference between the poloidal magnetic field and the proton flux oscillations, which are features of drift-bounce resonance. We estimate the resonance energy to ...

Oimatsu, S.; e, M.; Takahashi, K.; Yamamoto, K.; Keika, K.; Kletzing, C.; Smith, C.; MacDowall, R.; Mitchell, D.;

YEAR: 2018     DOI: 10.1029/2017JA025087

Van Allen Probes

Large-Amplitude Extremely Low Frequency Hiss Waves in Plasmaspheric Plumes

Su, Zhenpeng; Liu, Nigang; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2018     DOI: 10.1002/2017GL076754

electron instability; ELF hiss; generation mechanism; pitch angle scattering; precipitation loss; Radiation belt; Van Allen Probes

Prompt Disappearance and Emergence of Radiation Belt Magnetosonic Waves Induced by Solar Wind Dynamic Pressure Variations

Magnetosonic waves are highly oblique whistler mode emissions transferring energy from the ring current protons to the radiation belt electrons in the inner magnetosphere. Here we present the first report of prompt disappearance and emergence of magnetosonic waves induced by the solar wind dynamic pressure variations. The solar wind dynamic pressure reduction caused the magnetosphere expansion, adiabatically decelerated the ring current protons for the Bernstein mode instability, and produced the prompt disappearance of magn ...

Liu, Nigang; Su, Zhenpeng; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2018     DOI: 10.1002/2017GL076382

magnetosonic waves; Radiation belt; ring current; solar wind dynamic pressure; Van Allen Probes; Wave-particle interaction



  1      2      3