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The output plot filename has the standard format: tyymmddh1m1_h2m2.ext2.ext1.ptype where t stand for TIDE, yymmdd is the 2-digit year, month, and day-of-month of the plot start time, h1m1 are the start hour and minute, h2m2 are the stop hour and minute, ext2 is an optional file extension used to distinguish plots processed differently but with the same start/stop times, ext1 is the chromogram extension, and ptype is the plot type. If h2m2 is smaller than h1m1, the plot crosses a day boundary.
The chromogram plot file extension ext1 indicates which dimension was used where: polar channel is p, spin angle is s, and energy is e. The horizontal axis dimension is listed first, the vertical axis dimension second, and the color dimension third. So .esp is energy on the horizontal axis, spin angle on the vertical axis, and color based on polar angle. The other possible extensions are .pse, .pes, and .sep. Note: when color is based on energy or spin angle, polar angle is always plotted on the horizontal axis.
For 8-bit chromograms, IDL creates gif (.gif) and postscript (.ps) plot types (ptype). A pdf (.pdf) file was created from the postscript file because the .pdf file is much smaller but provides the same resolution. Thumbnail jpeg (.jpg) were created from the .gif files. For 24-bit chromograms, the IDL software creates plot types of .ps and .jpg because early IDL gif software did not support 24-bit color.
Samples of each type of chromogram for both the 8-bit and 24-bit color schemes can be found in /archive/tide_docs/ProcFiles/Chromo/Plots. The optional ext2 file extension was used to distinguish the 8-bit (.8bit) from the 24-bit (.24bit) chromograms.
As with most TIDE plots, there is some documentation at the bottom of the plot that includes the processing software version number; date the plot was created; plot filename; whether or not the minimum count was subtracted; the names for the sector sensitivity, calibration, and mass calibration files used in processing; source or value of the spacecraft potential used; and the names of the mask, attitude, orbit, and level-zero files used in the processing.
Above these are the time axis labels including time (hh:mm), Re, L-Shell, magnetic local time (mlt), magnetic (mlat) and invariant (invlat) latitude.
At the top left of the plot, the standard labeling includes the title line (POLAR TIDE/PSI), the start and stop times of the plot, the number of spins averaged, the data collapse option (see the TIDE Flight Software Requirements Document, page 10-13 for collapse option details), an indication that the spin data accumulation starts at the sun plus, and a plotted indication of the operational status (operational, standby, off, or mirror stepping) of both TIDE and PSI.
If the vertical axis is spin angle, the location of the ram (x), the positive (+) and the negative (-) magnetic field directions are indicated on the image.
At the upper-right of each plot are flux intensity color bar and the chromogram color wheel indicating the ranges of data used to determine the color and the colors that could appear on the chromogram image. If color is based on polar angle, the location of the minimum/maximum ram elevation (black) and the minimum/maximum magnetic elevation (white) are drawn on the color wheel.
Each panel represents a mass. There can be anywhere from 1 to 5 masses (H+, He+, O+, m/q 2, and/or NO+) on a plot.
The time axis is set up to display as much data as possible. The time axis is made up of a series of spin-averaged sets of data. Each spin is six seconds long. The number of spins averaged for each set of data on the plot depends on the user-specified length of time for the total plot and the dimension displayed on the horizontal axis. The start and stop times of the plot and the number of spins averaged for each set of data appears at the top left of a plot. If the horizontal axis is polar channel, there can be up to 35 spin averages on the horizontal axis. For spin angle and energy there can be up to 30 spin averages.
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Last Updated: September 2008