STIS CCD spectroscopic P-flats
نویسنده
چکیده
The analysis of the cycle 17 STIS CCD spectroscopic flats (Niemi 2010) pointed to the need to create a new dust mote image for the low resolution grating (L-mode) P-flats. This ISR describes the creation of the new L-mode P-flat from low resolution exposures taken during cycles 18 and 19. The document also analyzes the time dependence of the dust mote images as well as that of the intrinsic flat noise, comparing flat exposures collected since the start of operations. The effectiveness of the flat field correction is also tested and verified against high signal to noise observations of spectrophotometric standard stars. Recommendations are given for future observing strategies, flat fielding correction and future tests of the flat frames.
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