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The summary spectrograms included in this archive consist of seven spin-angle versus time panels per page; one panel for each of the seven mass/charge settings, H+, He+, O+, N+, M/Z=2, O++, and molecular ions. Noted at the top of each spectrogram is the date and time interval covered by the spectrogram, the instrument head, and indications of the RPA and aperture bias sort used. In this set, data were included regardless of RPA or aperture bias setting. Orbit parameters geocentric distance, McIlwain L-shell, magnetic local time, magnetic latitude, and invariant latitude are given at 40-min intervals at the bottom of the page.
The panels are labeled with mass designations (i.e., L/H+ for low mass channel, ionized hydrogen). Please note, however, that the data plotted represent the response of that RIMS channel to a specific range of mass/charge settings.
The satellite ram direction is defined to be along the center of each panel, meaning the point at which the radial detector was viewing into the direction of motion of the spacecraft. The maximum (180 degrees) and minimum (0 degrees) magnetic pitch angles are indicated by the black dashed and dotted lines (nearly horizontal, for the most part), respectively, corresponding to closest aperture approach to the parallel and anti-parallel directions of the Earth's magnetic field.
The data arrays used to construct each panel consist of 120 time divisions and 32 spin angle divisions. Since each spectrogram covers an 8-hour period, including a single 7.5-hour spacecraft orbital period, each angle/time bin represents a data average over 11.25 degrees in spin angle and 4 minutes of accumulation time. That is, the counts-per-accumulation periods (12 milliseconds), for all RPA and aperture bias settings, are averaged over the 4-min time resolution period for each 11.25 degree spin angle bin. The counts-per-sample for a given spin angle-time bin is coded by vertical lines; one solid vertical line representing low counts (0 to 1 count/sample) and many closely-spaced vertical lines (approaching solid black) representing higher count rates (>5000 counts/sample). A dotted vertical line represents an angle/time bin for which sampling occurred, but no counts were registered. No vertical lines at all indicates that sampling for that ion was not performed. The squares arranged vertically to the left of the spin angle-time panels show this scale.
The counts-per-sample is proportional to the integral directional ion flux for the energy range 0 to 50 eV with approximate conversion ratios of counts to integral flux of:
3.1x104 (particles/cm2/s/ster)/(counts/sample) for H+,
1.9x104 (particles/cm2/s/ster)/(counts/sample) for He+, and
4.4x104 (particles/cm2/s/ster)/(counts/sample) for O+.
These factors, which reflect the mass-dependent angular response, are based on pre-flight and in-flight calibration; the ratios are time-dependent due to on-orbit CEM degradation and are offered here only as a general approximation.
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