A5068197208- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Earthquake Detection and Analysis
- Geomagnetism and Paleomagnetism Studies
- Astro and Planetary Science
- Lightning and Electromagnetic Phenomena
- Planetary Science and Exploration
- Seismic Waves and Analysis
- GNSS positioning and interference
- Magnetic properties of thin films
- Underwater Acoustics Research
- Magnetic confinement fusion research
- Computational Physics and Python Applications
- Plasma Diagnostics and Applications
- Acoustic Wave Phenomena Research
- Tropical and Extratropical Cyclones Research
- Particle accelerators and beam dynamics
- Multiferroics and related materials
- Opportunistic and Delay-Tolerant Networks
- Ocean Waves and Remote Sensing
- Space Exploration and Technology
- Energy Harvesting in Wireless Networks
- Microfluidic and Bio-sensing Technologies
- Radio Astronomy Observations and Technology
- earthquake and tectonic studies
Boston University
2018-2025
Planetary Science Institute
2024
University of California, Los Angeles
2024
Dalian University of Technology
2021-2023
Hangzhou Dianzi University
2022-2023
Johns Hopkins University Applied Physics Laboratory
2023
Nanjing University of Posts and Telecommunications
2023
Case Western Reserve University
2022-2023
Dalian University
2023
Shandong University
2011-2020
Electromagnetic Ion Cyclotron (EMIC) waves can drive radiation belt depletion and Low-Earth Orbit (LEO) satellites detect the resulting electron proton precipitation. The ELFIN (Electron Losses Fields InvestigatioN) CubeSats provide an excellent opportunity to study properties of EMIC-driven precipitation with much higher energy pitch-angle resolution than previously allowed. We collect events from observations use POES (Polar Orbiting Environmental Satellites) search for 10s-100s keV nearby...
Abstract Electromagnetic ion cyclotron (EMIC) waves can drive precipitation of tens keV protons and relativistic electrons, are a potential candidate for causing radiation belt flux dropouts. In this study, we quantitatively analyze three cases EMIC‐driven precipitation, which occurred near the dusk sector observed by multiple Low‐Earth‐Orbiting (LEO) Polar Operational Environmental Satellites/Meteorological satellite programme (POES/MetOp) satellites. During EMIC wave activity, proton from...
Naturally occurring chorus emissions are a class of electromagnetic waves found in the space environments Earth and other magnetized planets. They play an essential role accelerating high-energy electrons forming hazardous radiation belt environment. Chorus typically occurs two distinct frequency bands separated by gap. The origin this two-band structure remains 50-year old question. Here we report, using NASA's Van Allen Probe measurements, that banded commonly accompanied separate...
Abstract We report the in situ observation of a plasma vortex induced by solar wind dynamic pressure enhancement nightside sheet using multipoint measurements from Time History Events and Macroscale Interactions during Substorms (THEMIS) satellites. The has scale 5–10 Re propagates several downtail, expanding while propagating. features are consistent with prediction Sibeck (1990) model, can penetrate deep (~8 ) dawn‐dusk direction couple to field line oscillations. Global...
Abstract We extend our database of whistler mode chorus, based on data from seven satellites, by including ∼3 years Radiation Belt Storm Probes (RBSP)‐A and RBSP‐B an additional ∼6 Time History Events Macroscale Interactions during Substorms (THEMIS)‐A, THEMIS‐D, THEMIS‐E. The new allows us to probe the near‐equatorial region in detail, revealing features. In equatorial source region, | λ m |<6°, strong wave power is most extensive 0.1–0.4 f c e bands 21–11 magnetic local time (MLT)...
Abstract Electromagnetic ion cyclotron (EMIC) waves are known to typically cause electron losses into Earth's upper atmosphere at >~1 MeV, while the minimum energy of electrons subject efficient EMIC‐driven precipitation loss is unresolved. This letter reports from subrelativistic energies ~250 keV up ~1 MeV observed by Focused Investigations Relativistic Electron Burst Intensity, Range and Dynamics (FIREBIRD‐II) CubeSats, two Polar Operational Environmental Satellites (POES) proton...
Abstract Very-Low-Frequency (VLF) transmitters operate worldwide mostly at frequencies of 10–30 kilohertz for submarine communications. While it has been intense scientific interest and practical importance to understand whether VLF can affect the natural environment charged energetic particles, decades there remained little direct observational evidence that revealed effects these in geospace. Here we report a radially bifurcated electron belt formation energies tens kiloelectron volts...
Abstract We present a global survey of energetic electron precipitation from the equatorial magnetosphere due to hiss waves in plasmasphere and plumes. Using Van Allen Probes measurements, we calculate pitch angle diffusion coefficients at bounce loss cone, evaluate energy spectrum precipitating flux. Our ∼6.5‐year shows that, during disturbed times, inside primarily causes L > 4 over 8 h < MLT 18 h, plumes cause 5 14 20 h. The flux increases with increasing geomagnetic activity, is...
Abstract Electromagnetic ion cyclotron waves in the Earth's outer radiation belt drive rapid electron losses through wave‐particle interactions. The precipitating flux can be high hundreds of keV energy range, well below typical minimum resonance energy. One proposed explanations relies on nonresonant scattering, which causes pitch‐angle diffusion away from fundamental resonance. Here we propose fractional sub‐cyclotron resonance, a second‐order nonlinear effect that scatters particles at...
Abstract Coronal mass ejection (CME)‐driven or corotating interaction region (CIR)‐driven storms can change the electron distributions in radiation belt dramatically, which turn affect spacecraft this induce geomagnetic effects. The Van Allen Probes twin spacecraft, launched on 30 August 2012, orbit near equatorial plane and across a wide range of L ∗ with apogee at 5.8 R E perigee 620 km. Electron data from MagEIS REPT instruments have been binned every 6 h =3 (defined as 2.5 < <3.5),...
Abstract The foreshock region involves localized and transient structures such as cavities hot flow anomalies due to solar wind‐bow shock interactions, transients have been shown lead magnetospheric ionospheric responses. In this paper, the interaction between a magnetosphere‐ionosphere system is investigated using dayside aurora imagers revealing propagation in greater detail than previously possible. A was detected by Time History of Events Macroscale Interactions during Substorms B C...
Abstract As one type of driver magnetospheric Alfvén waves, foreshock transients have received less attention than, for example, the Kelvin‐Helmholtz instability, discrete and broadband frequency solar wind dynamic pressure oscillations, interplanetary shocks. Previous works show that can induce both mode compressional Pc 3–5 ULF waves inside magnetosphere. However, to our knowledge, none these reported induced by transients, are proved be localized in In this paper, using situ ground‐based...
Abstract Whistler mode waves are important for precipitating energetic electrons into Earth's upper atmosphere, while the quantitative effect of each type whistler wave on electron precipitation is not well understood. In this letter, we evaluate driven by three types waves: plume waves, plasmaspheric hiss, and exohiss observed outside plasmapause. By quantitatively analyzing conjunction events between Van Allen Probes POES/MetOp satellites, together with quasi‐linear calculation, found that...
Abstract Whistler mode chorus waves can scatter plasma sheet electrons into the loss cone and produce Earth's diffuse aurora. Van Allen Probes observed electron injections intense on 24 November 2012. We use quasilinear theory to calculate precipitating fluxes, demonstrating that could lead high differential energy fluxes of with characteristic energies 10–30 keV. Using this method, we flux from 2012 2019 when were near magnetic equator perform global surveys precipitation under different...
Abstract Lightning generated whistlers (LGWs) play an important role in precipitating energetic electrons the Earth's inner radiation belt and beyond. Wave burst data from Van Allen Probes are used to unambiguously identify LGWs analyze their properties at L < 4 by extending frequencies down ~100 Hz for first time. The statistical results show that typically occur 100 10 kHz with major wave power below equatorial lower hybrid resonance frequency, amplitudes strong 3 occurrence rate up...
Abstract Advanced microfabrication gives rise to an extra degree of freedom for controlling magnetic textures, which determine the spin dynamics thin‐film magnets various spintronic devices. However, intuitive understanding complicated ferromagnetic resonances (FMRs) is still challenging lacking directly observed evolution inhomogeneous textures. This study demonstrates reconfigurable FMRs by introducing artificial patterns antidot lattices (namely magnonic crystals), mediated engineering...
Abstract Prompt enhancement of relativistic electron flux at L = 3–5 has been reported from Van Allen Probes Relativistic Electron Proton Telescope (REPT) measurements associated with the 17 March 2015 interplanetary shock compression dayside magnetosphere. Acceleration by ∼1 MeV is inferred on less than a drift timescale as seen in prior events, which launch magnetosonic azimuthal electric field impulse tailward. This propagates around flanks accelerating electrons resonance dusk flank....
Abstract The sudden enhancements of magnetic strength, named peaks (MPs), are often observed in the magnetosheath magnetized planets. They usually identified as flux ropes (FRs) or mirror mode structures. Previous studies MPs mostly on magnetohydrodynamics (MHD) scale. In this study, an electron scale MP is reported Earth magnetosheath. We present a typical case with ~7 gyroradii and duration ~0.18 s. A strong disturbance associated electrical current detected. Electron vortex found...
Abstract We report unusual Electromagnetic Ion Cyclotron (EMIC) waves with a very narrow frequency bandwidth, closely following and approaching the proton gyrofrequency. One interesting case analysis shows that magnetosonic waves, anisotropic suprathermal distributions, high EMIC are related. Magnetosonic potentially cause resonant heating of protons temperature anisotropy (10–100 eV) likely provides free energy for excitation waves. The statistical this type has typical wave amplitude ~100...
Abstract In this study, rapid loss of relativistic radiation belt electrons at low L * values (2.4–3.2) during a strong geomagnetic storm on 22 June 2015 is investigated along with five possible mechanisms. Both the particle and wave data are obtained from Van Allen Probes. Duskside H + band electromagnetic ion cyclotron (EMIC) waves were observed decrease energy above 5.2 MeV occurring outside plasmasphere extreme magnetopause compression. Lower He composition enriched O found compared to...
Abstract Precipitation into the Earth's atmosphere due to pitch angle scattering by plasma waves has been recognized as one of major loss mechanisms for energetic electrons. In this study, we quantitatively evaluate their roles in precipitating electrons during a conjunction event with modulated electron precipitation observed at low altitudes Electron Loss and Fields INvestigation three types whistler mode (hiss, plume hiss, chorus) measured near equator Time History Events Macroscale...
Abstract We statistically evaluate the global distribution and energy spectrum of electron precipitation at low‐Earth‐orbit, using unprecedented pitch‐angle resolved data from Electron Losses Fields INvestigation CubeSats. Our statistical results indicate that during active conditions, ∼63 keV ratio peaks L > 6 midnight, whereas spatial precipitating flux between dawn noon sectors. ∼1 MeV near midnight ∼6 but is enhanced dusk times. The shows reversal points indicating dispersion as a...
Abstract Energetic particle injections are commonly observed in Jupiter's magnetosphere and have important impacts on the radiation belts. We evaluate roles of electron dynamics whistler‐mode waves relativistic electrons using Juno measurements wave‐particle interaction modeling. The spacecraft injected flux bursts at energies up to 300 keV M shell ∼11 near magnetic equator during perijove‐31. related chorus wave 0.05–0.5 f ce frequencies, where is gyrofrequency. pitch angle distributions...