Ion data from the Plasma Composition Experiment on ISEE-1 consist of a combination of (a) velocity moments for the four principal magnetospheric ion species H+, He++, He+, and O+, calculated in two different ways (using two different sets of assumptions) and covering the 0.01-0.1 and 0.1-16 keV/e energy ranges, (b) energy-angle spectra for the same four ions plus O++, covering the 0.01-17.9 keV/e range, and (c) mass spectra (<1 amu/e to about 150 amu/e) for four energy ranges, all derived once per each complete energy-mass scan cycle of the instrument, or once each 1- to 20-minute interval, depending on mode of operation, as well as (d) "total ion" moments, derived once per energy scan and assuming total count rate is due to H+ ions (0.1-16 keV).
