The IRM plasma instrument (G. Paschmann, P.I.) consists of 2 sensors, one for ions and one for electrons, which measure the complete 3-D velocity distribution function in one spacecraft revolution. The energy range covered is 15eV - 30 keV for electrons and 20 eV/q - 40 keV/q for ions. Microcomputers within the experiment compute the moments of the distribution functions in real time. The main instrument characteristics are summarized below:
For more information see:
Paschmann, G., et al., The Plasma Instrument for AMPTE IRM, IEEE Trans. Geosci. Remote Sens., GE-23, 262, 1985.