ISPM SOLAR-WIND ION COMPOSITION SPECTROMETER.

The Solar-Wind Ion Composition Spectrometer (SWICS) instrument which will determine uniquely the elemental and ionic-charge composition, and the temperatures and mean speeds of all major solar-wind ions, from H through Fe, at solar wind speeds ranging from 145 km/s (protons) to 1352 km/s (Fe** plus **8). The instrument, which covers an energy per charge range from 110 ev/q to 66. 7 kev/q in approx. 13 min, combines an electrostatic analyzer with post-acceleration, followed by a time-of-flight and energy measurement. The measurements made by this instrument will have an impact on many areas of solar and heliospheric physics, in particular providing essential and unique information on: (i) conditions and processes in the region of the corona where the solar wind is accelerated; (ii) the location of the source regions of the solar wind in the corona (iii) coronal heating processes; (iv) the extent and causes of variations in the composition of the solar atmosphere; (v) plasma processes in the solar wind; (vi) the acceleration of energetic particles in the solar wind; (vii) the thermalization and acceleration of interstellar ions in the solar wind, and their composition; and (viii) the composition and behavior of the plasma in the Jovian magnetosphere.