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(Digel) This is just a flag defined to be True if the LAT is in the SAA. Right now it is not entirely clear (to me) whether we will be getting spacecraft position and attitude information during SAA passages. This would have implications, e.g., for using the Low-Rate Science counters to monitor the boundaries of the SAA, and also would mean that an IN_SAA flag would be superfluous. I'll update (or remove) this entry when I find out the answer.
(Digel) Here's word from Bryson Lee (4 April 2007): "The magic-7 data are sent out in the science data stream whenever the SIU is in application mode (after secondary boot) and the LIMMAINFEEDON command has been isued to power up the PDU and GASU. In effect, the data are available whenever the LAT is powered on, regardless of whether or not any events are being acquired."
So the IN_SAA flag remains relevant to the definition of FT2.
5. Extension Name for data extension in FITS file
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