Search Publications
Empirical reconstruction of storm time steady magnetospheric convection events
Anderson, B. J.; McPherron, R. L.; Sitnov, M. I. +4 more
We investigate the storm-scale morphology of the magnetospheric magnetic field as well as underlying distributions of electric currents, equatorial plasma pressure, and entropy for four steady magnetospheric convection (SMC) events that occurred during the May 2000 and October 2011 magnetic storms. The analysis is made using the empirical geomagne…
Jupiter's aurora in ultraviolet and infrared: Simultaneous observations with the Hubble Space Telescope and the NASA Infrared Telescope Facility
Bonfond, B.; Grodent, D.; Radioti, A. +2 more
We compare Jupiter's northern auroral emissions in infrared (IR) and ultraviolet (UV) using ground-based IR observations from the NASA Infrared Telescope Facility and UV observations from Hubble Space Telescope on 16 December 2000, the only date for which simultaneous observations in the two wavelength regions exist. We use polar projections and l…
Revision of empirical electric field modeling in the inner magnetosphere using Cluster data
Khotyaintsev, Yu. V.; Torbert, R. B.; Matsui, H. +2 more
Using Cluster data from the Electron Drift (EDI) and the Electric Field and Wave (EFW) instruments, we revise our empirically-based, inner-magnetospheric electric field (UNH-IMEF) model at 2<L<10. We pick more EFW data during large activities when wake effects are expected to be small. The model is organized by either the interplanetary elec…
The evolution of flux pileup regions in the plasma sheet: Cluster observations
Dandouras, I.; Nilsson, H.; André, M. +9 more
Bursty bulk flows (BBFs) play an important role for the mass, energy, and magnetic flux transport in the plasma sheet, and the flow pattern in and around a BBF has important consequences for the localized energy conversion between the electromagnetic and plasma mechanical energy forms. The plasma flow signature in and around BBFs is often rather c…
Hot flow anomaly formation and evolution: Cluster observations
Zong, Qiugang; Zhang, Hui; Wang, Shan
In this study, we have examined the formation and evolution of 513 hot flow anomalies (HFAs) from 2003 to 2009 observed by the Cluster spacecraft. Our results show that an original upstream discontinuity in the vicinity of an HFAs and/or at least one side of the HFA with the convective electric field pointing toward the discontinuity may help an H…
An MHD simulation model of time-dependent global solar corona with temporally varying solar-surface magnetic field maps
Hayashi, K.
We present a model of a time-dependent three-dimensional magnetohydrodynamics simulation of the sub-Alfvenic solar corona and super-Alfvenic solar wind with temporally varying solar-surface boundary magnetic field data. To (i) accommodate observational data with a somewhat arbitrarily evolving solar photospheric magnetic field as the boundary valu…
A statistical study of proton precipitation onto the Martian upper atmosphere: Mars Express observations
Barabash, S.; Nilsson, H.; Stenberg, G. +1 more
Due to the small size of the Martian magnetic pile-up region, especially at the subsolar point, heated protons with high enough energy can penetrate the induced magnetosphere boundary without being backscattered, i.e., they precipitate. We present a statistical study of the downgoing ~ keV proton fluxes measured in the Martian ionosphere by the An…
Response of Uranus' auroras to solar wind compressions at equinox
Cowley, S. W. H.
We consider open flux production and magnetic tail formation for the unique physical circumstances at Uranus, where the planet's spin axis lies close to the orbit plane, while the magnetic dipole has a large ~60° inclination to the spin axis. Under these circumstances, open flux production and transport into the nightside can in principle occur co…
Plasma particle simulations of wake formation behind a spacecraft with thin wire booms
Miyake, Y.; Usui, H.; Cully, C. M. +1 more
Double-probe electric field sensors installed on scientific spacecraft are often deployed using wire booms with radii much less than typical Debye lengths of magnetospheric plasmas (millimeters compared to tens of meters). However, in tenuous and cold-streaming plasmas seen in the polar cap and lobe regions, the wire booms, electrically grounded a…
Interplanetary and geomagnetic consequences of 5 January 2005 CMEs associated with eruptive filaments
Möstl, Christian; Srivastava, Nandita; Chakrabarty, D. +2 more
On 5 January 2005, SoHO/LASCO observed the launch of two successive coronal mass ejections (CMEs) associated with the filament (active region and quiescent) structures. The eruptions resulted in two distinct magnetic clouds whose embedded flux-rope topology is modeled by the Grad-Shafranov (G-S) reconstruction technique. Filament plasma remnants i…