Search Publications

Reconstruction of a large-scale reconnection exhaust structure in the solar wind
DOI: 10.5194/angeo-27-807-2009 Bibcode: 2009AnGeo..27..807T

Farrugia, C. J.; Hu, Q.; Teh, W. -L. +1 more

We recover two-dimensional (2-D) magnetic field and flow field configurations from three spacecraft encounters with a single large-scale reconnection exhaust structure in the solar wind, using a new reconstruction method (Sonnerup and Teh, 2008) based on the ideal single-fluid MHD equations in a steady-state, 2-D geometry. The reconstruction is pe…

2009 Annales Geophysicae
Cluster 28
On the triggering of auroral substorms by northward turnings of the interplanetary magnetic field
DOI: 10.5194/angeo-27-3559-2009 Bibcode: 2009AnGeo..27.3559W

Wild, J. A.; Woodfield, E. E.; Morley, S. K.

Some studies over the last decade have indicated that the instability responsible for substorm expansion phase onset may require an external trigger such as a northward turning of the interplanetary magnetic field (IMF). Statistical investigations have lead to contrasting interpretations regarding the relationship between proposed solar wind trigg…

2009 Annales Geophysicae
Cluster 26
Titan's ionosphere in the magnetosheath: Cassini RPWS results during the T32 flyby
DOI: 10.5194/angeo-27-4257-2009 Bibcode: 2009AnGeo..27.4257G

Gurnett, D. A.; Garnier, P.; Krimigis, S. M. +11 more

The Cassini mission has provided much information about the Titan environment, with numerous low altitude encounters with the moon being always inside the magnetosphere. The only encounter taking place outside the magnetopause, in the magnetosheath, occurred the 13 June 2007 (T32 flyby). This paper is dedicated to the analysis of the Radio and Pla…

2009 Annales Geophysicae
Cassini 26
Plasma transport in the magnetotail lobes
DOI: 10.5194/angeo-27-3577-2009 Bibcode: 2009AnGeo..27.3577H

Haaland, S.; Lybekk, B.; Pedersen, A. +4 more

The Earth's magnetosphere is populated by particles originating from the solar wind and the terrestrial ionosphere. A substantial fraction of the plasma from these sources are convected through the magnetotail lobes. In this paper, we present a statistical study of convective plasma transport through the Earth's magnetotail lobes for various geoma…

2009 Annales Geophysicae
Cluster 25
Cluster survey of the mid-altitude cusp - Part 2: Large-scale morphology
DOI: 10.5194/angeo-27-1875-2009 Bibcode: 2009AnGeo..27.1875P

Escoubet, C. P.; Pitout, F.; Dandouras, I. +1 more

In this second part of our statistical study of the mid-altitude cusp, we compare the cusp morphology, as seen in the Cluster ion spectrometer (CIS), to the interplanetary magnetic field (IMF) orientation. We first recall the method we have used a) to define the cusp properties, b) to sort IMF conditions or behaviour in classes, c) to determine th…

2009 Annales Geophysicae
Cluster 24
3-D reconstructions of the early-November 2004 CDAW geomagnetic storms: analysis of Ooty IPS speed and density data
DOI: 10.5194/angeo-27-4479-2009 Bibcode: 2009AnGeo..27.4479B

Jackson, B. V.; Buffington, A.; Hick, P. P. +4 more

Interplanetary scintillation (IPS) remote-sensing observations provide a view of the solar wind covering a wide range of heliographic latitudes and heliocentric distances from the Sun between ~0.1 AU and 3.0 AU. Such observations are used to study the development of solar coronal transients and the solar wind while propagating out through interpla…

2009 Annales Geophysicae
SOHO 21
Rosetta and Mars Express observations of the influence of high solar wind pressure on the Martian plasma environment
DOI: 10.5194/angeo-27-4533-2009 Bibcode: 2009AnGeo..27.4533E

Barabash, S.; Lundin, R.; Fränz, M. +18 more

We report on new simultaneous in-situ observations at Mars from Rosetta and Mars Express (MEX) on how the Martian plasma environment is affected by high pressure solar wind. A significant sharp increase in solar wind density, magnetic field strength and turbulence followed by a gradual increase in solar wind velocity is observed during ~24 h in th…

2009 Annales Geophysicae
MEx Rosetta 20
Evaluation of magnetic helicity density in the wave number domain using multi-point measurements in space
DOI: 10.5194/angeo-27-3967-2009 Bibcode: 2009AnGeo..27.3967N

Glassmeier, K. -H.; Narita, Y.; Kleindienst, G.

We develop an estimator for the magnetic helicity density, a measure of the spiral geometry of magnetic field lines, in the wave number domain as a wave diagnostic tool based on multi-point measurements in space. The estimator is numerically tested with a synthetic data set and then applied to an observation of magnetic field fluctuations in the E…

2009 Annales Geophysicae
Cluster 20
Substorm activity in Venus's magnetotail
DOI: 10.5194/angeo-27-2321-2009 Bibcode: 2009AnGeo..27.2321V

Barabash, S.; Futaana, Y.; Zhang, T. L. +5 more

The magnetotail of the induced magnetosphere of Venus is investigated through the magnetic field and plasma data of Venus Express. A comparison is made between two neutral sheet crossings. One crossing shows the magnetic field is rather quiet and the plasma instrument indicates a change from energetic (few 100 eV) to low energy (few 10 eV) ions. T…

2009 Annales Geophysicae
VenusExpress 18
MHD aspect of current sheet oscillations related to magnetic field gradients
DOI: 10.5194/angeo-27-417-2009 Bibcode: 2009AnGeo..27..417E

Kubyshkin, I. V.; Semenov, V. S.; Erkaev, N. V. +2 more

One-fluid ideal MHD model is applied for description of current sheet flapping disturbances appearing due to a gradient of the normal magnetic field component. The wave modes are studied which are associated to the flapping waves observed in the Earth's magnetotail current sheet. In a linear approximation, solutions are obtained for model profiles…

2009 Annales Geophysicae
Cluster 18