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AORKEY = 15070464
PI = Lei Hao
PROGID = 20741
PROTITLE = The mid-IR spectroscopy of the SDSS AGN
OBJECT = 18
PKUPACCU = High
PKUPFILT = BLUE
PKUPFLUX = 15.0000
PKUPXTND = 0
PTGDIFF (ACQ) = 0.072539214
PTGDIFF (SS) = 0.079557778
ACQ XC = 0
ACQ YC = 0
SS XC = 0
SS YC = 0
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EXPLANATION
The source is much fainter than expected, and so was not detected by the
onboard PU algorithm. A no-centroid alarm was generated in both ACQ
and SS. The source is visible in the PU image, and will have been moved
to the slit.