Search Publications
Formation of downstream high-speed jets by a rippled nonstationary quasi-parallel shock: 2-D hybrid simulations
Lu, Q.; Lembege, B.; Hao, Y. +1 more
Experimental observations from space missions (including more recently Cluster and Time History of Events and Macroscale Interactions during Substorms data) have clearly revealed the existence of high-speed jets (HSJs) in the downstream region of the quasi-parallel terrestrial bow shock. Presently, two-dimensional hybrid simulations are performed …
Origin of low proton-to-electron temperature ratio in the Earth's plasma sheet
Zelenyi, L. M.; Sauvaud, J. -A.; Lavraud, B. +4 more
We study the proton-to-electron temperature ratio (Tp/Te) in the plasma sheet (PS) of the Earth's magnetotail using 5 years of Cluster observations (2001-2005). The PS intervals are searched within a region defined with -19 < X ≤ -7 RE and |Y| < 15 RE (GSM) under the condition |BX| ≤ 10 …
On the propagation of a geoeffective coronal mass ejection during 15-17 March 2015
Webb, D. F.; Wang, Yuming; Shen, Fang +11 more
The largest geomagnetic storm so far, called 2015 St. Patrick's Day event, in the solar cycle 24 was produced by a fast coronal mass ejection (CME) originating on 15 March 2015. It was an initially west-oriented CME and expected to only cause a weak geomagnetic disturbance. Why did this CME finally cause such a large geomagnetic storm? We try to f…
Four-fluid MHD simulations of the plasma and neutral gas environment of comet 67P/Churyumov-Gerasimenko near perihelion
Hansen, Kenneth C.; Gombosi, Tamas I.; Combi, Michael R. +9 more
The neutral and plasma environment is critical in understanding the interaction of the solar wind and comet 67P/Churyumov-Gerasimenko (CG), the target of the European Space Agency's Rosetta mission. To serve this need and support the Rosetta mission, we have developed a 3-D four-fluid model, which is based on BATS-R-US (Block-Adaptive Tree Solarwi…
Properties of current sheet thinning at x ∼- 10 to -12 RE
Artemyev, A. V.; Runov, A.; Angelopoulos, V. +1 more
We report on Time History of Events and Macroscale Interactions during Substorms (THEMIS) observations of current sheet thinning in Earth's magnetotail at around x =- 10 to -12 Earth radii. The THEMIS spacecraft configuration in October-December 2015 allows us to construct both gradients that contribute to the cross-tail current density jy=µ…
A statistical study of plasmaspheric plumes and ionospheric outflows observed at the dayside magnetopause
Zhang, H.; Zong, Q. -G.; Rème, H. +3 more
We present a statistical study of plasmaspheric plumes and ionospheric outflows observed by the Cluster spacecraft near the dayside magnetopause. Plasmaspheric plumes are identified when the low-energy ions (<1 keV) with ∼90° pitch angle distributions are observed by the Cluster Ion Spectrometer/Hot Ion Analyzer instrument. The ionospheric outf…
Observation of an MHD Alfvén vortex in the slow solar wind
Alexandrova, O.; Li, B.; Li, X. +1 more
In the solar wind, magnetic field power spectra usually show several power laws. In this paper, magnetic field data from the Cluster mission during an undisturbed interval of slow solar wind are analyzed at 0.28 Hz, near the spectral break point between the ion inertial and dissipation/dispersion ranges. Assuming Taylor's frozen-in condition, it c…
Solar wind interaction with comet 67P: Impacts of corotating interaction regions
Glassmeier, K. -H.; Nilsson, H.; Henri, P. +18 more
We present observations from the Rosetta Plasma Consortium of the effects of stormy solar wind on comet 67P/Churyumov-Gerasimenko. Four corotating interaction regions (CIRs), where the first event has possibly merged with a coronal mass ejection, are traced from Earth via Mars (using Mars Express and Mars Atmosphere and Volatile EvolutioN mission)…
Empirical model of the Martian dayside ionosphere: Effects of crustal magnetic fields and solar ionizing flux at higher altitudes
Gurnett, D. A.; Němec, F.; Morgan, D. D. +1 more
We use electron density profiles measured by the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument on board the Mars Express spacecraft to investigate the effects of possible controlling parameters unconsidered in the empirical model of Němec et al. (2011, hereafter N11). Specifically, we focus on the effects of crustal magneti…
In situ observations of flux rope at the separatrix region of magnetic reconnection
Vaivads, A.; Retino, A.; Sahraoui, F. +12 more
We present the first in situ observations of a small-scale flux rope locally formed at the separatrix region of magnetic reconnection without large guide field. Bidirectional electron beams (cold and hot beams) and density cavity accompanied by intense wave activity substantiate the crossing of the separatrix region. Density compression and one pa…