Search Publications
Observed tail current systems associated with bursty bulk flows and auroral streamers during a period of multiple substorms
Dandouras, I.; Lucek, E.; Fazakerley, A. N. +10 more
We present a multi-instrument study of a substorm bursty bulk flow (BBF) and auroral streamer. During a substorm on 25 August 2003, which was one of a series of substorms that occurred between 00:00 and 05:00 UT, the Cluster spacecraft encountered a BBF event travelling Earthwards and duskwards with a velocity of ~500 km s-1 some nine m…
Magnetic clouds seen at different locations in the heliosphere
Zhukov, A. N.; Rodriguez, L.; Mandrini, C. H. +9 more
We analyze two magnetic clouds (MCs) observed in different points of the heliosphere. The main aim of the present study is to provide a link between the different aspects of this phenomenon, starting with information on the origins of the MCs at the Sun and following by the analysis of in-situ observations at 1 AU and at Ulysses. The candidate sou…
Plasma convection in the magnetotail lobes: statistical results from Cluster EDI measurements
Quinn, J.; Haaland, S.; Paschmann, G. +5 more
A major part of the plasma in the Earth's magnetotail is populated through transport of plasma from the solar wind via the magnetotail lobes. In this paper, we present a statistical study of plasma convection in the lobes for different directions of the interplanetary magnetic field and for different geomagnetic disturbance levels. The data set us…
Observations of recurrent cosmic ray decreases during solar cycles 22 and 23
Gómez-Herrero, R.; Heber, B.; Müller-Mellin, R. +5 more
During solar cycle 22, the modulation of several hundred MeV galactic cosmic rays (GCRs) by recurrent and transient cosmic ray decreases was observed by the Ulysses spacecraft on its descent towards the solar south pole. In solar cycle 23, Ulysses repeated this trajectory segment during a similar phase of the solar cycle, but with opposite heliosp…
Spatio-temporal structure of a poloidal Alfvén wave detected by Cluster adjacent to the dayside plasmapause
Pierrard, V.; Glassmeier, K. H.; Blomberg, L. G. +4 more
A case study of a poloidal ULF pulsation near the dayside plasmapause is presented based on Cluster observations of magnetic and electric fields. The pulsation is detected close to the magnetic equatorial plane at L shells L=[4.4, 4.6] and oscillates with a frequency of f=23 mHz. Investigating the wave energy flux reveals the standing wave nature …
Causal relationships between eruptive prominences and coronal mass ejections
Filippov, B.; Koutchmy, S.
A close association between eruptive prominences and CMEs, both slow and fast CMEs, was reported in many studies. Sometimes it was possible to follow the material motion starting from the prominence (filament) activation to the CME in the high corona. Remnants of the prominence were found in the bright core of the CME. However, detailed comparison…
Survey of ELF-VLF plasma waves in outer radiation belt observed by Cluster STAFF-SA experiment
Cornilleau-Wehrlin, N.; Pokhotelov, D.; Lefeuvre, F. +1 more
Various types of plasma waves have profound effects on acceleration and scattering of radiation belt particles. For the purposes of radiation belt modeling it is necessary to know statistical distributions of plasma wave parameters. This paper analyzes four years of plasma wave observations in the Earth's outer radiation belt obtained by the STAFF…
Formation of current density profile in tilted current sheets
Petrukovich, A. A.; Nakamura, R.; Baumjohann, W. +1 more
We investigate Cluster observations of strongly tilted sheets (flapping events) in the magnetotail. In accordance with the simple model of slip deformation (vertical differential displacement of neighboring flux tubes), the Jy current density component in the tilted sheet remains constant and equal to that in the horizontal undisturbed …
Why are CMEs large-scale coronal events: nature or nurture?
Mandrini, C. H.; van Driel-Gesztelyi, L.; Démoulin, P. +2 more
The apparent contradiction between small-scale source regions of, and large-scale coronal response to, coronal mass ejections (CMEs) has been a long-standing puzzle. For some, CMEs are considered to be inherently large-scale events eruptions in which a number of flux systems participate in an unspecified manner, while others consider magnetic reco…
Lower hybrid waves at the shock front: a reassessment
André, M.; Dunlop, M. W.; Walker, S. N. +3 more
The primary process occurring at a collisionless shock is the redistribution of the bulk upstream energy into other degrees of freedom. One part of this process results in the acceleration of electrons at the shock front. Accelerated electrons are observed at the terrestrial and other planetary shocks, comets, and their effects are observed in ast…