Search Publications
Simultaneous tracking of reconnected flux tubes: Cluster and conjugate SuperDARN observations on 1 April 2004
Lester, M.; Dunlop, M. W.; Taylor, M. G. G. T. +7 more
While the Cluster spacecraft were located near the high-latitude magnetopause, between 11:30-13:00 UT on 1 April 2004, a series of medium to large scale (40 nT, 0.6-1.2 Re) FTEs were observed. During this pass, simultaneous and conjugated SuperDARN measurements are available that show a global flow pattern which is consistent with the expected (ma…
Cluster observations of particle acceleration up to supra-thermal energies in the cusp region related to low-frequency wave activity - possible implications for the substorm initiation process
Dandouras, I.; Zhang, H.; Zong, Q. -G. +6 more
The purpose of our study is to investigate the way particles are accelerated up to supra-thermal energies in the cusp diamagnetic cavities. For this reason we have examined a number of Cluster cusp crossings, originally identified by Zhang et al. (2005), for the years 2001 and 2002 using data from RAPID, STAFF, EFW, CIS, PEACE, and FGM experiments…
Magnetic reconnection processes induced by a CME expansion
Romoli, M.; Bemporad, A.; Landini, F. +1 more
On 10 11 December 2005 a slow CME occurred in the Western Hemisphere in between two coronal streamers. SOHO/MDI magnetograms show a multipolar magnetic configuration at the photosphere: a complex of active regions located at the CME source and two bipoles at the base of the lateral coronal streamers. White light observations reveal that the CME ex…
Diagnostic of the temperature and differential emission measure (DEM) based on Hinode/XRT data
Siarkowski, M.; Falewicz, R.; Rudawy, P. +1 more
We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present the determination of the temperature distribution of the X-rays emitting plasma using a filters ratio method and three various methods of the calculation of …
Cluster observations on the thin current sheet in the magnetotail
Dandouras, I.; Rème, H.; Cao, J. B. +3 more
A magnetotail event on 15 September 2001 is analyzed, during which the Cluster spacecraft observed both embedding and bifurcation of the Thin Current Sheet (TCS). It is indicated that the ion anisotropy and nongyrotropy are responsible for those new equilibrium features that represent deviations from the conventional Harris model. Measurements sho…
Evaluation of bispectrum in the wave number domain based on multi-point measurements
Glassmeier, K. -H.; Décréau, P. M. E.; Narita, Y. +3 more
We present an estimator of the bispectrum, a measure of three-wave couplings. It is evaluated directly in the wave number domain using a limited number of detectors. The ability of the bispectrum estimator is examined numerically and then it is applied to fluctuations of magnetic field and electron density in the terrestrial foreshock region obser…
Diagnostics of active and eruptive prominences through hydrogen and helium lines modelling
Vial, J. -C.; Labrosse, N.; Gouttebroze, P.
In this study we show how hydrogen and helium lines modelling can be used to make a diagnostic of active and eruptive prominences. One motivation for this work is to identify the physical conditions during prominence activation and eruption. Hydrogen and helium lines are key in probing different parts of the prominence structure and inferring the …
Multi-instrument observations of a large scale Pc4 pulsation
Lucek, E. A.; Yeoman, T. K.; Clausen, L. B. N. +1 more
On 7 November 2005 various ground based and spaced based instruments registered five wave packets with frequencies in the Pc4 range. The most prominent of the five wave packets was observed in ground based magnetometer data spanning almost all latitudes on the dayside magnetosphere. The propagation from the dayside into the tail is deduced from Po…
Tailward propagation of Pi2 waves in the Earth's magnetotail lobe
Balogh, A.; Nakamura, R.; Baumjohann, W. +3 more
Pi2 waves are an intergral part of the substorm process and have been observed on the ground and in space. Using the special ability of Cluster to determine the propagation direction of signals measured in the magnetometer data, it is found that in the lobes of the Earth's magnetotail, for the cases in this study, the Pi2 waves are travelling tail…
Iterative inversion of global magnetospheric ion distributions using energetic neutral atom (ENA) images recorded by the NUADU/TC2 instrument
Barabash, S.; Dandouras, I.; Cao, J. B. +9 more
A method has been developed for extracting magnetospheric ion distributions from Energetic Neutral Atom (ENA) measurements made by the NUADU instrument on the TC-2 spacecraft. Based on a constrained linear inversion, this iterative technique is suitable for use in the case of an ENA image measurement, featuring a sharply peaked spatial distributio…