Articles | Volume 28, issue 2
Ann. Geophys., 28, 491–497, 2010

Special issue: Three eyes on the Sun – multi-spacecraft studies of...

Ann. Geophys., 28, 491–497, 2010

  09 Feb 2010

09 Feb 2010

Diagnostics of corotating interaction regions with the kinetic properties of iron ions as determined with STEREO/PLASTIC

P. Bochsler1,*, M. A. Lee1, R. Karrer2, L. K. Jian3, L. Ellis1, C. J. Farrugia1, A. B. Galvin1, L. M. Kistler1, H. Kucharek1, E. Möbius1, M. A. Popecki1, K. D. C. Simunac1, L. M. Blush2, H. Daoudi2, P. Wurz2, B. Klecker4, R. F. Wimmer-Schweingruber5, B. Thompson6, J. G. Luhmann7, C. T. Russell3, and A. Opitz8 P. Bochsler et al.
  • 1Space Science Center, University of New Hampshire, Durham, NH 03824, USA
  • 2Physikalisches Institut, University of Bern, 3012 Bern, Switzerland
  • 3Institute of Geophysics and Planetary Physics, UCLA, Los Angeles, CA 90024, USA
  • 4Max-Planck-Institut für extraterrestrische Physik, 85741 Garching, Germany
  • 5Institute for Experimental and Applied Physics, Christian-Albrechts-University, Leibnizstr. 11, 24098 Kiel, Germany
  • 6National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, MD 20771 USA
  • 7Space Science Laboratory, University of California, Berkeley, CA 94720, USA
  • 8Centre d'Etude Spatiale des Rayonnements (CNRS-UPS), 31028 Toulouse, France
  • *permanent address: Bahnhofstrasse 54, 3127 Mühlethurnen, Switzerland

Abstract. STEREO/PLASTIC determines three-dimensional distributions of solar wind iron ions with unprecedented time resolution. Typically 300 to 1000 counts are registered within each 5 min time interval. For the present study we use the information contained in these distributions to characterize CIRs (Corotating Interaction Regions) in two test cases. We perform a consistency test for both the derived physical parameters and for the analytical model of CIRs of Lee (2000). At 1 AU we find that apart from compositional changes the most indicative parameter for marking the time when a CIR passes a spacecraft is the angular deflection of the flow vector of particles. Changes in particle densities and the changes in magnitudes of speeds are apparently less reliable indicators of stream interfaces.