Search Publications
Electron acceleration in the Van Allen radiation belts by fast magnetosonic waves
Meredith, Nigel P.; Horne, Richard B.; Glauert, Sarah A. +3 more
Local acceleration is required to explain electron flux increases in the outer Van Allen radiation belt during magnetic storms. Here we show that fast magnetosonic waves, detected by Cluster 3, can accelerate electrons between ∼10 keV and a few MeV inside the outer radiation belt. Acceleration occurs via electron Landau resonance, and not Doppler …
In situ evidence of magnetic reconnection in turbulent plasma
André, M.; Vaivads, A.; Owen, C. J. +3 more
Magnetic reconnection is a universal process leading to energy conversion in plasmas. It occurs in the Solar System, in laboratory plasmas and is important in astrophysics . Reconnection has been observed so far only at large-scale boundaries between different plasma environments . It is not known whether reconnection occurs and is important in tu…
Reconnection of Magnetic Fields: Magnetohydrodynamics and Collisionless Theory and Observations
Priest, E. R.; Birn, J.
Preface; Part I. Introduction: 1.1 The Sun E. R. Priest; 1.2 Earth's magnetosphere J. Birn; Part II. Basic Theory of MHD Reconnection: 2.1 Classical theory of two-dimensional reconnection T. G. Forbes; 2.2 Fundamental concepts G. Hornig; 2.3 Three-dimensional reconnection in the absence of magnetic null points G. Hornig; 2.4 Three-dimensional reco…
Dissipation in Turbulent Plasma due to Reconnection in Thin Current Sheets
Retinò, Alessandro; Sundkvist, David; Vaivads, Andris +1 more
We present in situ measurements in a space plasma showing that thin current sheets the size of an ion inertial length exist and are abundant in strong and intermittent plasma turbulence. Many of these current sheets exhibit the microphysical signatures of reconnection. The spatial scale where intermittency occurs corresponds to the observed struct…
Ultralow frequency modulation of energetic particles in the dayside magnetosphere
Balogh, A.; Zong, Q. -G.; Baker, D. N. +8 more
Energetic electron and ion (electrons: 30 keV to 500 keV, protons: 30 keV to 1.5 MeV) flux variations associated with ultralow frequency (ULF) waves in the dayside magnetosphere were observed during the CLUSTER's perigee pass near 0900 MLT on Oct. 31, 2003. The ULF modulation terminated where higher frequency fluctuations appeared, as the CLUSTER …
Magnetospheric configurations from a high-resolution data-based magnetic field model
Sitnov, M. I.; Tsyganenko, N. A.
We present first results of the magnetospheric magnetic field modeling, based on large sets of spacecraft data and a high-resolution expansion for the field of equatorial currents. In this approach, the field is expanded into a sum of orthogonal basis functions of different scales, capable to reproduce arbitrary radial and azimuthal variations of …
Evidence for an Elongated (>60 Ion Skin Depths) Electron Diffusion Region during Fast Magnetic Reconnection
Eastwood, J. P.; Phan, T. D.; Mozer, F. S. +2 more
Observations of an extremely elongated electron diffusion region occurring during fast reconnection are presented. Cluster spacecraft in situ observations of an expanding reconnection exhaust reveal a broad current layer (∼10 ion skin depths thick) supporting the reversal of the reconnecting magnetic field together with an intense current embedded…
Energetic electron acceleration in the downstream reconnection outflow region
Balogh, A.; RèMe, H.; Daly, P. W. +5 more
Energetic electrons in an earthward reconnection outflow region have been observed by Cluster/Research with Adaptive Particle Imaging Detectors. We found a good correlation between the energetic electron enhancement and a normal magnetic field (Bz) enhancement within a 0.25-s time resolution. The large normal magnetic field is thought t…
Multi-point observations of the Hall electromagnetic field and secondary island formation during magnetic reconnection
Balogh, A.; Dandouras, I.; Eastwood, J. P. +7 more
A key feature of collisionless magnetic reconnection is the formation of Hall magnetic and electric field structure in the vicinity of the diffusion region. Here we present multi-point Cluster observations of a reconnection event in the near-Earth magnetotail where the diffusion region was nested by the Cluster spacecraft; we compare observations …
Evidence for magnetic reconnection initiated in the magnetosheath
Eastwood, J. P.; Lucek, E. A.; Rème, H. +6 more
We report Cluster spacecraft 1 observations of a reconnection exhaust embedded in the magnetosheath flow. The reconnection evidence consists of (1) accelerated plasma outflows, (2) interpenetrating ion beams, (3) reconnection inflows and (4) the associated tangential reconnection electric field. Furthermore, Hall magnetic fields were observed with…