Extraction Slits for First-Order STIS Spectra
نویسندگان
چکیده
ABSTRACT: Measurements of enclosed energy vs. extraction slit height and numerical simulations for first-order STIS spectra demonstrate the dependence of signal-to-noise (S/N) on the extraction slit height for different gratings, wavelengths, and signal levels. Slit heights of 11 pixels for G140L and G230L, and 7 pixels for the three CCD first-order modes are a reasonable compromise between photometric precision, achieved S/N, and spectral purity at most wavelengths. We recommend the implementation of these extraction slits for the pipeline and the default absolute flux calibration of archival STIS spectra of point sources.
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تاریخ انتشار 1998