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Drift-Bounce Resonance Between Charged Particles and Ultralow Frequency Waves: Theory and Observations
Zong, Qiu-Gang; Liu, Ying; Zhang, Shuai +7 more
Ultralow frequency (ULF) waves have long been known to resonate with magnetospheric charged particles through their drift and bounce motions. Most research interest has focused on the resonance with drift motion, which can accelerate charged particles at very high energies. The role of the bounce motion, especially for particles with lower energie…
Outer Radiation Belt Electron Lifetime Model Based on Combined Van Allen Probes and Cluster VLF Measurements
Aryan, Homayon; Boynton, Richard; Balikhin, Michael A. +4 more
The flux of energetic electrons in the outer radiation belt shows a high variability. The interactions of electrons with very low frequency (VLF) chorus waves play a significant role in controlling the flux variation of these particles. Quantifying the effects of these interactions is crucially important for accurately modeling the global dynamics…
Temporal and Spectral Studies by XMM-Newton of Jupiter's X-ray Auroras During a Compression Event
Coates, A. J.; Jackman, C. M.; Branduardi-Raymont, G. +16 more
We report the temporal and spectral results of the first XMM-Newton observation of Jupiter's X-ray auroras during a clear magnetospheric compression event on June 2017 as confirmed by data from the Jovian Auroral Distributions Experiment (JADE) instrument onboard Juno. The northern and southern auroras were visible twice and thrice respectively as…
Evolution of High-Speed Jets and Plasmoids Downstream of the Quasi-Perpendicular Bow Shock
Gunell, H.; Hamrin, M.; Goncharov, O. +1 more
Plasma structures with enhanced dynamic pressure, density, or speed are often observed in Earth's magnetosheath. We present a statistical study of these structures, known as jets and fast plasmoids, in the magnetosheath, downstream of both the quasi-perpendicular and quasi-parallel bow shocks. Using measurements from the four Magnetospheric Multis…
The Deflection of Coronal Mass Ejections by the Ambient Coronal Magnetic Field Configuration
Liu, Siqing; Wang, Jingjing; Hoeksema, J. Todd
Solar coronal mass ejections (CMEs) are sometimes deflected during their propagation. This deflection may be the consequence of an interaction between the CME and the ambient coronal field, for example, a coronal hole, or the solar wind. The coronal magnetic field configuration is computed from daily synoptic maps of magnetic field from SOHO/MDI a…
The Influence of Varying Spacecraft Potentials and Debye Lengths on In Situ Low-Energy Ion Measurements
Stenberg Wieser, Gabriella; Wieser, Martin; Eriksson, Anders +2 more
Low-energy ions are difficult to measure, mainly due to spacecraft charging. The ions are attracted to or repelled from the charged surface prior to detection, which changes both the energy and travel direction of the ions. This results in distortions of the data, and the changed travel directions distort the effective field of view (FOV) of the i…
Jovian Auroral Ion Precipitation: X-Ray Production From Oxygen and Sulfur Precipitation
Cravens, T. E.; Mauk, B. H.; Dunn, W. R. +6 more
Many attempts have been made to model X-ray emission from both bremsstrahlung and ion precipitation into Jupiter's polar caps. Electron bremsstrahlung modeling has fallen short of producing the total overall power output observed by Earth-orbit-based X-ray observatories. Heavy ion precipitation was able to reproduce strong X-ray fluxes, but the pr…
Martian Ionopause Boundary: Coincidence With Photoelectron Boundary and Response to Internal and External Drivers
Gurnett, D. A.; Morgan, D. D.; Halekas, J. +8 more
The Martian ionopause boundary detected as steep gradients in the local electron density profiles from the Mars Advanced Radar for Subsurface and Ionospheric Sounder on Mars Express is studied individually and statistically and compared to the photoelectron boundary identified by the drop of photoelectron signature due to CO2 and O mole…
An Enhancement of Jupiter's Main Auroral Emission and Magnetospheric Currents
Wilson, R. J.; Kurth, W. S.; Bagenal, F. +9 more
We present observations of Jupiter's magnetic field and plasma obtained with the NASA Juno spacecraft during February 2018, along with simultaneous Hubble Space Telescope (HST) observations of the planet's auroras. We show that a few-day transient enhancement of the azimuthal and radial magnetic fields and plasma temperature was coincident with a …
Foreshock Bubbles at Venus: Hybrid Simulations and VEX Observations
Omidi, N.; Collinson, G.; Sibeck, D.
In the absence of a global magnetic field at Venus, its ionosphere is the obstacle to the flow of the solar wind resulting in the formation of a smaller bow shock and foreshock. Spacecraft observations and global hybrid (kinetic ions, fluid electrons) simulations have demonstrated that despite its smaller size, the foreshock at Venus has propertie…