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Magnetic phase structure of Saturn's 10.7 h oscillations
Dougherty, M. K.; Yates, J. N.; Southwood, D. J.
A source of Saturn's magnetic 10.7 h period oscillations has yet to be identified. The oscillations are known to consist of signals with slightly different periods from separate northern and southern sources. Here we present a novel way of examining observations, focusing on signal phase. We show that although the signals are highly periodic they …
Comment on "Magnetic phase structure of Saturn's 10.7 h oscillations" by Yates et al.
Andrews, D. J.; Cowley, S. W. H.; Provan, G.
Cluster observations of unusually high concentration of energetic O+ carried by flux ropes in the nightside high-latitude magnetosheath during a storm initial phase
Dandouras, I.; Reme, H.; Lui, A. T. Y. +6 more
We present measurements from Cluster spacecraft to investigate the energetic singly charged oxygen ions, O+, within the flux ropes in the nightside high-latitude magnetosheath during the initial phase of an intense storm on 24 October 2011. Three magnetic flux ropes were identified by Cluster 4 in the intervals from 20:10 UT to 20:20 UT…
Magnetospheric signatures of ionospheric density cavities observed by Cluster
Karlsson, T.; Wright, A. N.; Russell, A. J. B.
We present Cluster measurements of large amplitude electric fields correlated with intense downward field-aligned currents, observed during a nightside crossing of the auroral zone. The data are reproduced by a simple model of magnetosphere-ionosphere coupling which, under different conditions, can also produce a divergent electric field signature…
The use of the power density for identifying reconnection regions
Gunell, H.; Hamrin, M.; Vaivads, A. +2 more
In the vicinity of magnetic reconnection, magnetic energy is transferred into kinetic energy. A reconnection region hence corresponds to a load, and it should manifest itself as large and positive values of the power density, E·J ≫ 0, where E is the electric field and J the current density. In this article we analyze Cluster plasma sheet data from…
Electron density and parallel electric field distribution of the auroral density cavity
Karlsson, T.; Marklund, G. T.; Alm, L.
We present an event study in which Cluster satellites C1 and C3 encounters the flux tube of a stable auroral arc in the premidnight sector. C1 observes the midcavity, while C3 enters the flux tube of the auroral arc at an altitude which is below the acceleration region, before crossing into the top half of the acceleration region. This allows us t…
Dawn-dusk asymmetry in bursty hot electron enhancements in the midtail magnetosheath
Wang, Chih-Ping; Nakamura, T. K. M.; Lyons, Larry R. +1 more
Bursty (a few minutes) enhancements of hot electrons (1-10 keV) in the tail magnetosheath, which we name hot electron enhancements (HEEs), are sometimes observed. To understand the processes leading to HEEs, we have used 4 years of measurements from Acceleration Reconnection Turbulence and Electrodynamics of Moon's Interaction with the Sun mission…
Magnetopause orientation: Comparison between generic residue analysis and BV method
Dorville, Nicolas; Belmont, Gérard; Rezeau, Laurence +2 more
Determining the direction normal to the magnetopause layer is a key step for any study of this boundary. Various techniques have been developed for this purpose. We focus here on generic residue analysis (GRA) methods, which are based on conservation laws, and the new iterative BV method, where B represents the magnetic field and V refers to the i…
Right-handed circularly polarized dispersive Alfvén wave: Localization and turbulence in solar wind
Sharma, R. P.; Gaur, Nidhi; Sharma, Swati
The elucidation of the turbulent spectrum in the solar wind region in the dispersive range of scales is not yet completely established. The observational analysis of many spacecraft report that the fluctuations on the order of (or smaller scales) proton inertial length λi = c/ω p i show disparity with respect to the large-sca…
Whistlers observed outside the plasmasphere: Correlation to plasmaspheric/plasmapause features
Gallagher, D. L.; Adrian, M. L.; Fung, S. F. +1 more
Whistlers observed outside the plasmasphere by Cluster have been correlated with the global plasmasphere using Imager for Magnetopause-to-Aurora Global Exploration-Extreme Ultraviolet Imager (IMAGE-EUV) observations. Of the 12 Cluster-observed whistler events reported, EUV is able to provide global imaging of the plasmasphere for every event and d…