Search Publications
Propagation of lower-band whistler-mode waves in the outer Van Allen belt: Systematic analysis of 11 years of multi-component data from the Cluster spacecraft
Santolík, Ondřej; Cornilleau-Wehrlin, Nicole; Kolmašová, Ivana +2 more
Lower-band whistler-mode emissions can influence the dynamics of the outer Van Allen radiation belts. We use 11 years of measurements of the STAFF-SA instruments onboard the four Cluster spacecraft to systematically build maps of wave propagation parameters as a function of position. We determine probability distributions of wave vector angle weig…
Wave activities in separatrix regions of magnetic reconnection
Fujimoto, Keizo
Two-dimensional particle-in-cell simulations have reproduced the waves consistent with those observed frequently in the separatrix regions of magnetic reconnection in the Earth's magnetotail. The key process generating the waves is intense parallel acceleration of the electrons due to an electrostatic potential hump formed in the inflow side of th…
First observation of rising-tone magnetosonic waves
Santolík, O.; Chen, L.; Cao, J. B. +7 more
Magnetosonic (MS) waves are linearly polarized emissions confined near the magnetic equator with wave normal angle near 90° and frequency below the lower hybrid frequency. Such waves, also termed equatorial noise, were traditionally known to be "temporally continuous" in their time-frequency spectrogram. Here we show for the first time that MS wav…
Cold electron heating by EMIC waves in the plasmaspheric plume with observations of the Cluster satellite
Dandouras, Iannis; Yuan, Zhigang; Huang, Shiyong +7 more
We report in situ observations by the Cluster spacecraft of plasmaspheric electron heating in the plasmaspheric plume. Electron heating events were accompanied by enhancements of electromagnetic ion cyclotron (EMIC) waves in the increased density ducts on the negative density gradient side for two substructures of the plasmaspheric plume. Electron…
Observation of double layer in the separatrix region during magnetic reconnection
Zhang, Tielong; Li, Xing; Huang, Can +11 more
We present in situ observation of double layer (DL) and associated electron measurement in the subspin time resolution in the separatrix region during reconnection for the first time. The DL is inferred to propagate away from the X line at a velocity of about ion acoustic speed and the parallel electric field carried by the DL can reach -20 mV/m. …
Fast transport of resonant electrons in phase space due to nonlinear trapping by whistler waves
Krasnoselskikh, V.; Artemyev, A. V.; Agapitov, O. V. +4 more
We present an analytical, simplified formulation accounting for the fast transport of relativistic electrons in phase space due to wave-particle resonant interactions in the inhomogeneous magnetic field of Earth's radiation belts. We show that the usual description of the evolution of the particle velocity distribution based on the Fokker-Planck e…
Global model of low-frequency chorus (fLHR<f<0.1fce) from multiple satellite observations
Meredith, Nigel P.; Horne, Richard B.; Thorne, Richard M. +2 more
Whistler mode chorus is an important magnetospheric emission, playing a dual role in the acceleration and loss of relativistic electrons in the Earth's outer radiation belt. Chorus is typically generated in the equatorial region in the frequency range 0.1-0.8 fce, where fce is the local electron gyrofrequency. However, as the…
Highly structured electron anisotropy in collisionless reconnection exhausts
Torbert, R. B.; Li, G.; Chen, L. -J. +6 more
Results from two-dimensional particle-in-cell simulations of collisionless magnetic reconnection with zero guide field discussed in this paper reveal that around the time when the reconnection rate peaks, electron velocity distributions become highly structured in magnetic islands and open exhausts. Rings, arcs, and counterstreaming beams are gene…
Increases in plasma sheet temperature with solar wind driving during substorm growth phases
Jackman, C. M.; Dandouras, I.; Fazakerley, A. N. +10 more
During substorm growth phases, magnetic reconnection at the magnetopause extracts ~1015 J from the solar wind which is then stored in the magnetotail lobes. Plasma sheet pressure increases to balance magnetic flux density increases in the lobes. Here we examine plasma sheet pressure, density, and temperature during substorm growth phase…
Evidence of strong energetic ion acceleration in the near-Earth magnetotail
Fränz, M.; Wei, Y.; Daly, P. W. +6 more
Until now it is still questionable whether ions are accelerated to energies above 100 keV in the near-Earth current sheet (CS), in the vicinity of a possible near-Earth neutral line. By using 11 years of 3-D energetic ion flux data for protons, helium, and oxygen (~150 keV-1 MeV) from the RAPID instrument on board Cluster 4, we statistically study…