Search Publications
Electric structure of dipolarization front at sub-proton scale
André, M.; Vaivads, A.; Huang, S. Y. +2 more
Using Cluster data, we investigate the electric structure of a dipolarization front (DF) - the ion inertial length (c/ωpi) scale boundary in the Earth's magnetotail formed at the front edge of an earthward propagating flow with reconnected magnetic flux. We estimate the current density and the electron pressure gradient throughout the D…
Occurrence rate of earthward-propagating dipolarization fronts
André, M.; Vaivads, A.; Huang, S. Y. +2 more
The occurrence rate of earthward-propagating dipolarization fronts (DFs) is investigated in this paper based on the 9 years (2001-2009) of Cluster 1 data. For the first time, we select the DF events by fitting the characteristic increase in Bz using a hyperbolic tangent function. 303 earthward-propagating DFs are found; they have on ave…
Recent advances in understanding substorm dynamics
Nakamura, R.; Sergeev, V. A.; Angelopoulos, V.
Magnetospheric substorms are elemental processes of solar wind energy storage and explosive release in Earth's magnetosphere. They encompass fundamental plasma physics questions, are ubiquitous during all types of geomagnetic conditions, contribute significantly to magnetic storms, and are a key element of Space Weather applications. This paper re…
Low-energy ions: A previously hidden solar system particle population
André, M.; Cully, C. M.
Ions with energies less than tens of eV originate from the Terrestrial ionosphere and from several planets and moons in the solar system. The low energy indicates the origin of the plasma but also severely complicates detection of the positive ions onboard sunlit spacecraft at higher altitudes, which often become positively charged to several tens…
Electron acceleration in the reconnection diffusion region: Cluster observations
André, M.; Vaivads, A.; Sahraoui, F. +10 more
We present one case study of magnetic islands and energetic electrons in the reconnection diffusion region observed by the Cluster spacecraft. The cores of the islands are characterized by strong core magnetic fields and density depletion. Intense currents, with the dominant component parallel to the ambient magnetic field, are detected inside the…
Observations of turbulence within reconnection jet in the presence of guide field
André, M.; Vaivads, A.; Sahraoui, F. +8 more
We present the first comprehensive observations of turbulence properties within high speed reconnection jet in the plasma sheet with moderate guide field. The power spectral density index is about -1.73 in the inertial range, and follows the value of -2.86 in the ion dissipation range. The turbulence is strongly anisotropic in the wave-vector spac…
Magnetotail dipolarization front and associated ion reflection: Particle-in-cell simulations
Shay, M. A.; Wu, P.
For the Earth magnetotail, the Svenes et al. (2008) statistical study infers the lobe density to be highly variable, in the range of 0.007-0.092 cm-3. Such lobe density variation modifies reconnection diffusion region physical processes and reconnection rate drastically. This letter addresses observable reconnection signatures in the vi…
Electron pitch-angle diffusion in radiation belts: The effects of whistler wave oblique propagation
Krasnoselskikh, V.; Breuillard, H.; Agapitov, O. +2 more
We calculated the electron pitch-angle diffusion coefficients in the outer radiation belt for L-shell ∼4.5 taking into account the effects of oblique whistler wave propagation. The dependence of the distribution of the angle θ between the whistler wave vector and the background magnetic field on magnetic latitude is modeled after statistical resul…
On the ionospheric source region of cold ion outflow
Fränz, M.; Wei, Y.; Daly, P. W. +8 more
Recent studies have shown that low energy ions constitute a significant part of the total ion population in the Earth's magnetosphere. In this study, we have used a comprehensive data set with measurements of cold (total energy less than 70 eV) ion velocity and density to determine their source. This data set is derived from Cluster satellite meas…
Correction to “A statistical study of the propagation characteristics of whistler waves observed by Cluster”
Khotyaintsev, Yuri V.; Agapitov, Oleksiy; Krasnoselskikh, Vladimir +1 more
Abstract Available from http://www.agu.org