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 …
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 …
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…
Nonstationarity and reformation of high-Mach-number quasiperpendicular shocks: Cluster observations
Dunlop, M.; Schwartz, S. J.; Krasnoselskikh, V. V. +3 more
A set of experimental data is presented for a high-Mach-number (M f = 5) quasiperpendicular ($\theta$ Bn = 81°) bow shock layer crossed by Cluster spacecraft on 24 January 2001 at 07:05-07:09 UT. The measurements of magnetic field, spectra of electric field fluctuations, and ion distributions reveal that the shock is high…
Strong bulk plasma acceleration in Earth's magnetosheath: A magnetic slingshot effect?
Thomsen, M. F.; Lavraud, B.; Fazakerley, A. N. +5 more
In the near-Earth environment, strong bulk plasma accelerations are frequently taken to be the diagnostic of the occurrence of magnetic reconnection. In this letter, we report new and unambiguous spacecraft observations and corresponding magnetohydrodynamic (MHD) simulation of strong bulk plasma acceleration in the terrestrial magnetosheath during…
Global view of dayside magnetic reconnection with the dusk-dawn IMF orientation: A statistical study for Double Star and Cluster data
Lucek, E.; Dunlop, M. W.; Rème, H. +14 more
Double Star/TC-1 and Cluster data show that both component reconnection and anti-parallel reconnection occur at the magnetopause when the interplanetary magnetic field (IMF) is predominantly dawnward. The occurrence of these different features under these very similar IMF conditions are further confirmed by a statistical study of 290 fast flows me…
SAID: Plasmaspheric short circuit of substorm injections
Mishin, E. V.; Puhl-Quinn, P. A.
We present magnetically-conjugate Cluster/DMSP observations of subauroral ion drifts (SAID) after the onset of a weak substorm on 18 March 2002 that confirm and expand on the previous Cluster/DMSP results. The outer side of the SAID channel is aligned with the plasmapause and its outer edge marks the dispersionless boundary of the electron precipi…
Source of whistler emissions at the dayside magnetopause
André, M.; Stenberg, G.; Vaivads, A. +4 more
Observations of whistler emissions are common in the magnetosphere near the dayside magnetopause. We show that one of the major source regions for these emissions is magnetic field minima that form along magnetic flux tubes at high latitudes. Using multispacecraft Cluster observations we experimentally confirm for the first time the existence of t…
A Cluster measurement of fast magnetic reconnection in the magnetotail
Escoubet, C. P.; Balogh, A.; Dandouras, I. +11 more
Fast reconnection is crucial to magnetospheric substorms, solar and stellar flares and fusion plasmas. Ultimate confirmation of fast reconnection must be achieved by multi-spacecraft detections of the reconnection rate itself and associated dimensions of the diffusion region. Here we report a multi-spacecraft measurement of fast reconnection rate …
Flow burst-induced Kelvin-Helmholtz waves in the terrestrial magnetotail
Zhang, T. L.; Glassmeier, K. -H.; Lucek, E. +7 more
The Kelvin-Helmholtz instability (KHI) on the boundary of a flow channel in the Earth's plasma sheet is investigated using Cluster and Double Star TC1 data. It is shown that when Cluster moves into the flow channel the magnetometer measures strong oscillations of the magnetic field, that increase as the spacecraft move further into the flow channe…