Articles | Volume 23, issue 8
Ann. Geophys., 23, 2757–2774, 2005

Special issue: Double Star - First Results

Ann. Geophys., 23, 2757–2774, 2005

  08 Nov 2005

08 Nov 2005

The HIA instrument on board the Tan Ce 1 Double Star near-equatorial spacecraft and its first results

H. Rème1, I. Dandouras1, C. Aoustin1, J. M. Bosqued1, J. A. Sauvaud1, C. Vallat1, P. Escoubet2, J. B. Cao3, J. Shi3, M. B. Bavassano-Cattaneo4, G. K. Parks5, C. W. Carlson5, Z. Pu6, B. Klecker7, E. Moebius8, L. Kistler8, A. Korth9, R. Lundin10, and the HIA team H. Rème et al.
  • 1Centre d’Etude Spatiale des Rayonnements (CESR), Toulouse, France
  • 2European Space Research and Technology Center (ESTEC), ESA, The Netherland
  • 3Center for Space Science and Applied Research (CSSAR), Beijing, China
  • 4Istituto di Fisica dello Spazio Interplanetario (IFSI), Roma, Italy
  • 5Space Sciences Laboratory (SSL), Berkeley, USA
  • 6Peking University, Beijing, China
  • 7Max-Planck-Institut für extraterrestrische Physik (MPE), Garching, Germany
  • 8University of New Hampshire (UNH), Durham, USA
  • 9Max Planck Institute for Solar System Research (MPS), Lindau, Germany
  • 10Swedish Institute of Space Physics (IRF), Kiruna, Sweden

Abstract. On 29 December 2003, the Chinese spacecraft Tan Ce 1 (TC-1), the first component of the Double Star mission, was successfully launched within a low-latitude eccentric orbit. In the framework of the scientific cooperation between the Academy of Sciences of China and ESA, several European instruments, identical to those developed for the Cluster spacecraft, were installed on board this spacecraft.

The HIA (Hot Ion Analyzer) instrument on board the TC-1 spacecraft is an ion spectrometer nearly identical to the HIA sensor of the CIS instrument on board the 4 Cluster spacecraft. This instrument has been specially adapted for TC-1. It measures the 3-D distribution functions of the ions between 5 eV/q and 32 keV/q without mass discrimination.

TC-1 is like a fifth Cluster spacecraft to study the interaction of the solar wind with the magnetosphere and to study geomagnetic storms and magnetospheric substorms in the near equatorial plane.

HIA was commissioned in February 2004. Due to the 2 RE higher apogee than expected, some in-flight improvements were needed in order to use HIA in the solar wind in the initial phase of the mission. Since this period HIA has obtained very good measurements in the solar wind, the magnetosheath, the dayside and nightside plasma sheet, the ring current and the radiation belts. We present here the first results in the different regions of the magnetosphere and in the solar wind. Some of them are very new and include, for example, ion dispersion structures in the bow shock and ion beams close to the magnetopause. The huge interest in the orbit of TC-1 is strongly demonstrated.