Search Publications
Conjugate observation of sharp dynamical boundary in the inner magnetosphere by Cluster and DMSP spacecraft and ground network
Nakamura, R.; Sergeev, V. A.; Baumjohann, W. +9 more
We investigate an unusual sharp boundary separating two plasma populations (inner magnetospheric plasma with high fluxes of energetic particles and plasma sheet) observed by the Cluster quartet near its perigee on 16 December 2003. Cluster was in a pearl-on-string configuration at 05:00 MLT and mapped along magnetic field lines to ~8 9 RE
Structure of the near-Earth plasma sheet during tailward flows
Balogh, A.; Nakamura, R.; Fujimoto, M. +10 more
A detailed analysis of successive tailward flow bursts in the near-Earth magnetotail (X~-19 RE) plasma sheet is performed on the basis of in-situ multi-point observations by the Cluster spacecraft on 15 September 2001. The tailward flows were detected during a northward IMF interval, 2.5 h after a substorm expansion. Each flow burst (V<…
Non-thermal particle effects on the Hα and Hβ line profiles in the 18 August 2002 solar flare
Kashapova, L. K.; Kotrč, P.; Kupryakov, Yu. A.
We present results of the 18 August 2002 flare analysis as an example for developing a diagnostic tool for thermal and non-thermal processes in chromospheric lines. Taking into account the hard X-ray (HXR) emission, we attempted to derive the Hα and Hβ line properties which were caused by the non-thermal electron contribution and could be useful f…
Momentum transfer at the high-latitude magnetopause and boundary layers
Farrugia, C. J.; Lund, E. J.; Sandholt, P. E.
The Hall current system revealed as a statistical significant pattern during fast flows
Nakamura, R.; Snekvik, K.; Østgaard, N. +2 more
We have examined the dawn-dusk component of the magnetic field, BY, in the night side current sheet during fast flows in the neutral sheet. 237 h of Cluster data from the plasma sheet between 2 August 2002 and 2 October 2002 have been analysed. The spatial pattern of BY as a function of the distance from the centre of the cur…
Ionospheric signatures during a magnetospheric flux rope event
Owen, C. J.; Nakamura, R.; Sergeev, V. +6 more
On 13 August 2002, during a substorm, Cluster encountered two earthward moving flux ropes (FR) in the central magnetotail. The first FR was observed during the expansion phase of the substorm, and the second FR during the recovery phase. In the conjugate ionospheric region in Northern Fennoscandia, the ionospheric equivalent currents were observed…
A general Cluster data and global MHD simulation comparison
Daum, P.; Wild, J. A.; Taylor, M. G. G. T. +3 more
Among the many challenges facing the space weather modelling community today, is the need for validation and verification methods of the numerical models available describing the complex nonlinear Sun-Earth system. Magnetohydrodynamic (MHD) models represent the latest numerical models of this environment and have the unique ability to span the eno…
Magnetosphere-ionosphere coupling during periods of extended high auroral activity: a case study
Kistler, L. M.; Karlsson, T.; Mouikis, C. +6 more
Results are presented from a case study of a plasma boundary crossing by the Cluster spacecraft during an extended period of high auroral activity. The boundary between the magnetotail lobe region of the Southern Hemisphere and the plasma sheet boundary layer, was characterized by intense electric and magnetic field variations, structured upward a…
Quantifying and containing the curse of high resolution coronal imaging
Delouille, V.; Hochedez, J. -F.; Chainais, P.
Future missions such as Solar Orbiter (SO), InterHelioprobe, or Solar Probe aim at approaching the Sun closer than ever before, with on board some high resolution imagers (HRI) having a subsecond cadence and a pixel area of about (80 km)2 at the Sun during perihelion. In order to guarantee their scientific success, it is necessary to ev…
A case study of dayside reconnection under extremely low solar wind density conditions
Dandouras, I.; Rème, H.; Maggiolo, R. +2 more
From 15 February 2004, 20:00 UT to 18 February 2004, 01:00 UT, the solar wind density dropped to extremely low values (about 0.35 cm-3). On 17 February, between 17:45 UT and 18:10 UT, the CLUSTER spacecraft cross the dayside magnetopause several times at a large radial distance of about 16 RE. During each of these crossings, …