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We have engaged in the development of a software package for the automated reduction of CCD images taken as part of a wide-field objective-prism survey for extragalactic emission-line sources. The survey, called KISS (KPNO International Spectroscopic Survey), is an international collaborative effort to survey for emission-line galaxies (ELGs) to B = 20 -- 21 over large areas of the sky. It utilizes the 0.61-m Burrell Schmidt telescope located at KPNO with an objective prism and a large-format CCD detector, and selects objects via the presence of strong line emission. The survey technique used yields 20--30 ELG candidates per square degree, which is 200--300 times the surface density of the Markarian survey. \smallskip
The KISS reduction package was designed to run under the IRAF image processing environment, and will eventually grow to be a complete IRAF package. Tasks operate on pairs of images for each field, one direct image and one spectral image. The direct image, taken with the prism removed, is used to locate all objects in the the field; it is typically 1 magnitude (or more) deeper than the corresponding spectral image. The software locates automatically all objects in the direct image, performs a coordinate transformation to align the direct and spectral images, extracts the spectra of all objects in the spectral images including applying full corrections for overlapping spectra, and then searches the extracted 1D spectra for emission-line candidates. The output consists of an STSDAS ``ttools" format file which contains the extracted spectra, coordinates, and magnitudes of all ELG candidates. Additional tasks are available for examining the processed data. \smallskip
Although The KISS survey is directed towards finding emission-line objects, the software developed could be easily used for other digital objective-prism surveys.
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