Search Publications
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…
Contribution of Anisotropic Electron Current to the Magnetotail Current Sheet as a Function of Location and Plasma Conditions
Petrukovich, A. A.; Russell, C. T.; Artemyev, A. V. +7 more
The magnetotail current sheet carries the current responsible for the largest fraction of the energy storage in the magnetotail, the magnetic energy in the lobes. It is thus inextricably linked with the dynamics and evolution of many magnetospheric phenomena, such as substorms. The magnetotail current sheet structure and stability depend mostly on…
Simultaneous Observations of ELF/VLF Rising-Tone Quasiperiodic Waves and Energetic Electron Precipitations in the High-Latitude Upper Ionosphere
Lei, Jungang; Zhima, Zeren; Huang, Jianping +12 more
The quasiperiodic (QP) waves accompanied by simultaneous energetic electron precipitations in the high-latitude ionosphere were recorded by the sun-synchronous circular orbit China Seismo-Electromagnetic Satellite (CSES). The new features of QP waves observed by CSES are the well-pronounced rising-tone structures and very short repetition periods,…
Multiscale MHD-Kinetic PIC Study of Energy Fluxes Caused by Reconnection
Lapenta, Giovanni; Berchem, Jean; Walker, Raymond +1 more
We present an analysis of the energy partitioning in the magnetotail during a substorm at 03:58:00 UT on 7 February 2009. The analysis employs a multiscale approach where we use a state from a global magnetohydrodynamics (MHD) model to spawn a kinetic particle-in-cell (PIC) simulation of a large portion of the tail. We directly investigate the ene…
Ionosphere Feedback to Electron Scattering by Equatorial Whistler Mode Waves
Artemyev, A. V.; Runov, A.; Shen, Y. +5 more
Plasma sheet electron precipitation, much of it driven by whistler mode waves, is critical for magnetosphere-ionosphere coupling. This precipitation leads to a secondary electron population at low altitudes, which moves upward along magnetic field lines to the equatorial plasma sheet. We investigate observational evidence for such electron precipi…
Jupiter's X-ray Emission During the 2007 Solar Minimum
Jackman, C. M.; Paranicas, C.; Ness, J. -U. +22 more
The 2007-2009 solar minimum was the longest of the space age. We present the first of two companion papers on Chandra and XMM-Newton X-ray campaigns of Jupiter through February-March 2007. We find that low solar X-ray flux during solar minimum causes Jupiter's equatorial regions to be exceptionally X-ray dim (0.21 GW at minimum; 0.76 GW at maximum…
Prebreakup Arc Intensification due to Short Circuiting of Mesoscale Plasma Flows Over the Plasmapause
Mishin, Evgeny; Streltsov, Anatoly
The prebreakup arc at the inner edge of the auroral boundary is intensified upon arrival of an auroral streamer—the ionospheric signature of the earthbound mesoscale plasma flows (MPF). Yet the cause of electron precipitation enhancement only in this region remains unclear. We suggest that the intensified precipitation comes from the turbulent pla…