Ion distribution dynamics near the Earth's bow shock: first measurements with the 2D ion energy spectrometer CORALL on the INTERBALL/Tail-probe satellite

Abstract

Abstract. The dynamics of the ion distribution function near the Earth's bow shock is studied on the basis of quasi-3D measurements of ion energy spectra in the range of 30±24200 eV/q with the Russian-Cuban COR-ALL instrument on the INTERBALL/Tail-probe satellite. The instrument was designed for observations of magnetospheric plasma and measures ions, in an angular range of 36°±144°from the Earth-Sun direction. Ion populations generated by the Earth bow shock are often observed upstream from the bow shock. In the solarwind stream compressed and heated by the passing of very dense magnetic cloud (CME), two types of these ion populations were measured upstream and before the bow shock crossing on 25 August 1995 at 07:37 UT. Both populations were observed in the energy range above 2 keV. At $06:20 UT, when the angle between the direction of the interplanetary magnetic ®eld and normal to the bow shock 5 fn was 9 43 the instrument observed a narrow, fast ($800 km/s) ®eld-aligned beam moving from the Earth. At $07:30, when 5 fn 9 28 , the wide ion pitch-angle distribution was observed. A similar suprathermal ion population is observed in the magnetosheath simultaneously with the solar-wind ion population being heated and de¯ected from the SunEarth direction. The similarity of observations during the mentioned time-interval and under usual solar-wind conditions allows us to conclude that types of suprathermal ion populations upstream and downstream from the bow shock do not depend on the solar-wind disturbance generated by magnetic cloud.

The magnetopause shape and location: a comparison of the Interball and Geotail observations with models

“…Interball-1 and Magion-4 magnetopause crossings were identified manually on the basis of observations of ion and electron energy spectra (Yermolaev et al, 1997;Sauvaud et al, 1997;Nemecek et al, 1997) and the magnetic field (Nozdrachev et al, 1998). Geotail magnetopause crossings were computed automatically on the basis of the magnetic field changes (Ivchenko et al, 2000).…”

Interball-tail observations of vertical plasma motions in the magnetotail

“…The ion spectrometer CORALL (Yermolaev et al, 1997) on board the Interball-Tail (IT) spacecraft detected ion flux in the energy range 0.05-25 keV with the use of the 2D fivesector electrostatic analyzer. The whole 3D ion distribution function was scanned during the spacecraft spin.…”

Correlated Interball/ground-based observations of isolated substorm: The pseudobreakup phase

“…In this study, we present observations by CORALL, ELECTRON, DOK-2 and MIF-M experiments onboard the Interball-1 spacecraft. CORALL is the nearly-hemispheric electrostatic analyzer which measured the ions with energies 0.3-24 keV/q (Yermolaev et al, 1997). ELECTRON (Sauvaud et al, 1997) is a "top-hat" quadri-spherical electron spectrometer that uses the microchannel plates to measure the electrons with energies ranging from 0.01 to 26 keV.…”