Articles | Volume 25, issue 11
Ann. Geophys., 25, 2439–2451, 2007
Ann. Geophys., 25, 2439–2451, 2007

  29 Nov 2007

29 Nov 2007

Internal structure and spatial dimensions of whistler wave regions in the magnetopause boundary layer

G. Stenberg1,2, T. Oscarsson1,†, M. André2, A. Vaivads2, M. Backrud-Ivgren2,3, Y. Khotyaintsev2, L. Rosenqvist2, F. Sahraoui4, N. Cornilleau-Wehrlin4, A. Fazakerley5, R. Lundin6, and P. M. E. Décréau7 G. Stenberg et al.
  • 1Department of Physics, Umeå University, Umeå, Sweden
  • 2Swedish Institute of Space Physics, Uppsala, Sweden
  • 3Division of Plasma Physics, Alfvén Laboratory, Royal Institute of Technology, Stockholm, Sweden
  • 4CETP/UVSQ, Vélizy, France
  • 5MSSL, University College, London, UK
  • 6Swedish Institute of Space Physics, Kiruna, Sweden
  • 7LPCE et Université d'Orléans, France
  • deceased

Abstract. We use whistler waves observed close to the magnetopause as an instrument to investigate the internal structure of the magnetopause-magnetosheath boundary layer. We find that this region is characterized by tube-like structures with dimensions less than or comparable with an ion inertial length in the direction perpendicular to the ambient magnetic field. The tubes are revealed as they constitute regions where whistler waves are generated and propagate. We believe that the region containing tube-like structures extend several Earth radii along the magnetopause in the boundary layer. Within the presumed wave generating regions we find current structures moving at the whistler wave group velocity in the same direction as the waves.