This preliminary ASCA SIS Source Catalog contains a list of point sources detected by the Solid-state Imaging Spectrometers (SIS) on-board the ASCA Observatory. This catalog was generated by searching for point-like sources in all data available from the HEASARC's ASCA public archive (ASCAPUBLIC) as of 24 Oct 1996; and is populated by both target and serendipitous sources in the SIS field-of-view. For each catalogued source various information is available, which includes the celestial coordinates of the source, the count rate, the significance of detection, and the hardness ratio, total aperture counts, exposure time, and start time of the observation. In addition, a set of three GIF "thumbnail" images is available in the broad (0.5 - 12 keV), soft (2 < keV), and hard (> 2 keV) spectral bands centered on the apparent detection. These images are convenient for accessing the quality of the source detection. The current catalog is preliminary, the goal of the catalog authors being to make the SIS source list available as quickly as possible. To accomplish this, they took an incremental approach and placed their "work in progress" on-line, warts and all. They urge caution in using and citing these preliminary results, as they point out that the information is not, as yet, 100% reliable. This catalog was generated in January 1997 by Drs. Eric Gotthelf and Nicholas White and resulted from their search for point-like sources in all of the then-available SIS data files in the HEASARC's Public ASCA Data Archive as of 24 Oct 1996. The catalog is populated with both targeted and serendipitous sources that were present in the SIS field-of-view. This is a service provided by NASA HEASARC .
