Search Publications
Radio-loud CMEs from the disk center lacking shocks at 1 AU
MacDowall, R. J.; Kaiser, M. L.; Gopalswamy, N. +4 more
A coronal mass ejection (CME) associated with a type II burst and originating close to the center of the solar disk typically results in a shock at Earth in 2-3 days and hence can be used to predict shock arrival at Earth. However, a significant fraction (about 28%) of such CMEs producing type II bursts were not associated with shocks at Earth. We…
Short large-amplitude magnetic structures (SLAMS) at Venus
Coates, A. J.; Barabash, S.; Zhang, T. L. +5 more
We present the first observation of magnetic fluctuations consistent with short large-amplitude magnetic structures (SLAMS) in the foreshock of the planet Venus. Three monolithic magnetic field spikes were observed by the Venus Express on 11 April 2009. The structures were ∼1.5-11 s in duration, had magnetic compression ratios between ∼3 and 6, an…
Determining the axial direction of high-shear flux transfer events: Implications for models of FTE structure
Milan, S. E.; Fear, R. C.; Oksavik, K.
Flux transfer events are bursts of dayside reconnection, which give rise to local perturbations of the magnetic field that can be observed by spacecraft near the magnetopause. Although it is commonly accepted that flux transfer events are caused by reconnection, various models exist to explain their structure. A key difference between mechanisms i…
Identification of electron field-aligned current systems in Saturn's magnetosphere
Schippers, P.; André, N.; Gurnett, D. A. +3 more
Based on the analysis of 7 years of Cassini electron plasma spectrometer data near Saturn's equatorial plane, we computed the average directional electron current in the Northern and the Southern hemispheres separately. We determined the net current density by subtracting the downward electron current density (equator to the ionosphere) from the u…
A statistical study of energy release and transport midway between the magnetic reconnection and initial dipolarization regions in the near-Earth magnetotail associated with substorm expansion onsets
Paterson, W. R.; Miyashita, Y.; Saito, Y. +3 more
Our previous study showed that the energy release associated with substorm expansion onsets is the most significant midway between the magnetic reconnection and initial dipolarization regions (-12 > X > -18 RE in the premidnight sector) in the magnetotail. In the present paper, we have statistically studied the substorm-associated…
Bow shock and magnetopause contributions to the magnetospheric current system: Hints from the Cluster observations
Wang, C.; Tang, B. B.; Guo, X. C.
We perform a statistical study of the surface current at the high-latitude magnetopause (HLMP) and the bow shock under different southward interplanetary magnetic field (IMF) conditions, taking advantage of the crossing events of these discontinuities by the Cluster spacecraft. With an enhancement of southward IMF BZ, the surface curren…
A physical model for electron radiation belts of Saturn
Lorenzato, Lise; Sicard, AngéLica; Bourdarie, SéBastien
Radiation belts cause irreversible damages to on-board instrument materials. Studies about radiation belts can provide precious information for future interplanetary missions. Pioneer 11, Voyager 2 and nowadays Cassini missions give the characteristics of Saturn's inner magnetosphere: Saturn's famous rings, various moons, neutral particles ejected…
Whistler anisotropy instability with a cold electron component: Linear theory
Gary, S. Peter; Liu, Kaijun; Denton, Richard E. +1 more
The whistler anisotropy instability is driven by an electron temperature anisotropy T⊥/T∥ > 1 where ⊥ and ∥ denote directions perpendicular and parallel, respectively, to the background magnetic field Bo. Here kinetic linear theory in a magnetized, homogeneous, collisionless plasma model is used to study this in…
Multidimensional nonlinear mirror-mode structures in the Earth's magnetosheath
Omura, Yoshiharu; Shoji, Masafumi; Lee, Lou-Chuang
We performed two-dimensional (2D) and three-dimensional (3D) hybrid simulations in open boundary models to study the nonlinear mirror-mode structures driven by the temperature anisotropy (T⊥/T∥> 1) of protons in the magnetosheath. In the open systems, because of the propagation of EMIC waves, we obtain the clearer non-prop…
Magnetic flux rope formation within a magnetosheath hot flow anomaly
Zhang, H.; Zong, Q. -G.; Lavraud, B. +4 more
We report observations on 1 March 2004 by the Cluster spacecraft of a hot flow anomaly (HFA) encountered in the dayside magnetosheath near Earth's bow shock. Embedded within the HFA was a magnetic flux rope with a diameter of a few thousand km, which was moving sunward and was presumably expanding. The pristine upstream solar wind seen by the ACE …