Search Publications

Anomalous magnetosheath flows and distorted subsolar magnetopause for radial interplanetary magnetic fields
DOI: 10.1029/2009GL039842 Bibcode: 2009GeoRL..3618112S

Glassmeier, K. H.; Plaschke, F.; McFadden, J. P. +5 more

On 12 August 2007 from 1436 to 1441 UT, when the five THEMIS probes (THA, THB, THC, THD, and THE) were located near the subsolar magnetopause, a sunward flow was observed in the magnetosheath. A fast anti-sunward flow (-280 km/s) was observed in the magnetosheath before the sunward flow. Although THA observed this fast anti-sunward flow, THC and T…

2009 Geophysical Research Letters
Cluster 90
Source regions of banded chorus
DOI: 10.1029/2009GL037629 Bibcode: 2009GeoRL..3611101B

Pickett, J. S.; Inan, U. S.; Bell, T. F. +1 more

ELF/VLF chorus emissions are very intense electromagnetic plasma waves that are naturally and spontaneously excited near the magnetic equatorial plane outside the plasmasphere during periods of magnetic disturbance. These emissions are believed to play an important role in the acceleration of 10 to 100 keV radiation belt electrons to MeV energies …

2009 Geophysical Research Letters
Cluster 56
Regions associated with electron physics in asymmetric magnetic field reconnection
DOI: 10.1029/2009GL037463 Bibcode: 2009GeoRL..36.7102M

Pritchett, P. L.; Mozer, F. S.

Spatial relationships between regions containing signatures of electron physics in asymmetric reconnection with a guide field are examined using simulations and space observations that are in excellent agreement. These electron physics regions do not completely overlap, are not confined to sizes ∼electron skin depth, and do not surround the X-line…

2009 Geophysical Research Letters
Cluster 29
Stochastic and direct acceleration mechanisms in the Earth's magnetotail
DOI: 10.1029/2008GL036619 Bibcode: 2009GeoRL..36.4103P

Perri, S.; Zimbardo, G.; Greco, A.

Ion beams with energies of the order of several tens of keV are frequently observed in the Earth's magnetotail. Here we consider two possible acceleration mechanisms, the cross tail electric field E y and the stochastic acceleration due to the electromagnetic fluctuations present in the magnetotail. Electromagnetic perturbations are g…

2009 Geophysical Research Letters
Cluster 26
Tracing solar wind plasma entry into the magnetosphere using ion-to-electron temperature ratio
DOI: 10.1029/2009GL039442 Bibcode: 2009GeoRL..3618109L

Berchem, J.; Escoubet, C. P.; Dandouras, I. +22 more

When the solar wind Mach number is low, typically such as in magnetic clouds, the physics of the bow shock leads to a downstream ion-to-electron temperature ratio that can be notably lower than usual. We utilize this property to trace solar wind plasma entry into the magnetosphere by use of Cluster measurements in the vicinity of the dusk magnetop…

2009 Geophysical Research Letters
Cluster 23
A magnetospheric generator driving ion and electron acceleration and electric currents in a discrete auroral arc observed by Cluster and DMSP
DOI: 10.1029/2009GL038343 Bibcode: 2009GeoRL..3612111E

Roth, M.; De Keyser, J.; Maggiolo, R. +1 more

Simultaneous observations on April 28, 2001 by Cluster and DMSP-F14 reveal a stable discrete auroral arc and fluxes of field-aligned accelerated electrons and ions coincident with a magnetospheric plasma interface at an altitude of 4.5 RE in the dusk sector. We compare satellite data with a quasi-stationary magnetosphere-ionosphere coup…

2009 Geophysical Research Letters
Cluster 18
Cavities of weak magnetic field strength in the wake of FTEs: Results from global magnetospheric MHD simulations
DOI: 10.1029/2009GL037489 Bibcode: 2009GeoRL..3610104K

Toth, G.; Hesse, M.; Wang, Y. +4 more

We use the global magnetohydrodynamic (MHD) code BATS-R-US to model multipoint observations of Flux Transfer Event (FTE) signatures. Simulations with high spatial and temporal resolution predict that cavities of weak magnetic field strength protruding into the magnetosphere trail FTEs. These predictions are consistent with recently reported multi-…

2009 Geophysical Research Letters
Cluster 11
Magnetopause reconnection impact parameters from multiple spacecraft magnetic field measurements
DOI: 10.1029/2009GL040228 Bibcode: 2009GeoRL..3620108W

Wendel, Deirdre E.; Reiff, Patricia H.

We present a novel technique that exploits multiple spacecraft data to determine the impact parameters of the most general form of magnetic reconnection at the magnetopause. The method consists of a superposed epoch of multiple spacecraft magnetometer measurements that yields the instantaneous magnetic spatial gradients near a magnetopause reconne…

2009 Geophysical Research Letters
Cluster 5
Reconnection Hall current system observed in the magnetotail and in the ionosphere
DOI: 10.1029/2009GL037239 Bibcode: 2009GeoRL..36.8104S

Snekvik, K.; Østgaard, N.; Amm, O. +1 more

On 07 Sep 2001 around 21:40 UT, Cluster was located 19 R E downtail, and observed earthward fast flows and strong perturbations in the dawn-dusk component of the magnetic field (B Y ). The perturbations corresponded to a sheet of tailward field aligned current close to the neutral sheet and another sheet of earthward field…

2009 Geophysical Research Letters
Cluster 2