Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 1.490
IF1.490
IF 5-year value: 1.445
IF 5-year
1.445
CiteScore value: 2.9
CiteScore
2.9
SNIP value: 0.789
SNIP0.789
IPP value: 1.48
IPP1.48
SJR value: 0.74
SJR0.74
Scimago H <br class='widget-line-break'>index value: 88
Scimago H
index
88
h5-index value: 21
h5-index21
Volume 19, issue 10/12
Ann. Geophys., 19, 1579–1587, 2001
https://doi.org/10.5194/angeo-19-1579-2001
© Author(s) 2001. This work is distributed under
the Creative Commons Attribution 3.0 License.

Special issue: CLUSTER

Ann. Geophys., 19, 1579–1587, 2001
https://doi.org/10.5194/angeo-19-1579-2001
© Author(s) 2001. This work is distributed under
the Creative Commons Attribution 3.0 License.

  30 Sep 2001

30 Sep 2001

Preliminary two-point observations of the mid-altitude cusp by Cluster PEACE and FGM

I. Krauklis1, A. N. Fazakerley1, C. J. Owen1, P. J. Carter1, M. W. Dunlop2, A. J. Coates1, S. Szita1, M. G. G. T. Taylor1, P. Travnicek1, G. Watson1, and R. J. Wilson1 I. Krauklis et al.
  • 1Mullard Space Science Laboratory, Department of Space and Climate Physics, University College London, UK
  • 2Blackett Laboratory, Imperial College of Science Technology and Medicine, London, UK

Abstract. On 1 October 2000, Cluster spacecraft Samba (Cluster 3) and Tango (Cluster 4) made an outbound crossing of the northern mid-altitude (4.7 RE) cusp region, moving roughly parallel to the noon meridian. We present preliminary observations from this interval made by the PEACE and FGM instruments. The interplanetary magnetic field at the magnetopause is estimated to have turned south at the time of our observations, based on ACE data as well as a rough estimate of the time taken for the solar wind to travel between ACE and the magnetopause. Cluster 3 encountered the low-latitude boundary layer (LLBL) between 12:20:30 to 12:26:00 UT, and the cusp region between 12:26:00 and 12:32:30 UT. Cluster 4 encountered the LLBL between 12:22:00 to 12:29:00 UT, and the cusp region between 12:29:00 and 12:38:00 UT. During the interval between the two spacecraft passages through these regions, the open/closed field line boundary was observed to move equatorward by 0.33° invariant latitude, while the latitudinal extent of the cusp region increased by 0.5°. Both of these observations are consistent with the ongoing reconnection at the sub-solar magnetopause. The magnetic field data indicate that Cluster encountered four field-aligned longitudinally extended current sheets. The most equatorward of these is consistent with the location of a Region 1 current sheet. Two current sheets were observed in the vicinity of the cusp region, though neither of these were thin current sheets. The fourth current sheet was observed in the mantle region and was largely unaffected by the latitudinal expansion of the cusp region.

Key words. Magnetospheric physics (current systems; energetic particles, precipitating; magnetopause, cusp and boundary layers)

Publications Copernicus
Special issue
Download
Citation