What constitutes a Good Time Interval (GTI) (OTHER than a jaunt to the local pub)?
GTIs are those times when all of the quality conditions for good data are satisfied. Non-GTIs occur whenever any of the conditions are not satisfied: poor aspect quality, inappropriate viewing geometry (too close to an Earth limb for example), high voltage off, etc. The 2nd table in the photon list .FITS file lists the temporal status flags that tell why a particular time interval was rejected.
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