The Web Version of the McCook-Sion White Dwarf Catalog contains in excess of 500 more entries than the previous published version, the 4th Edition (1999) of the Villanova White Dwarf Catalog. It is a catalog of white dwarfs which have been identified spectroscopically. For each degenerate star, the following data entries with references are provided: (1) catalog coordinate designation or WD number, (2) the right ascension and declination, (3) the spectral type based upon the new system, (4) a catalog symbol denoting binary membership, (5) proper motion and position angle, (6) broad-band UBV Photometry, V, B-V, U-B, (7) multichannel spectrophotometry, V(MC), g-r, (8) Stromgren narrow-band photometry y, b-y, u-b, (9) an absolute visual magnitude based upon the best available color-magnitude calibration or trigonometric parallax, (10) the observed radial velocity uncorrected for gravitational redshift or solar motion, and (11) the trigonometric parallax, with mean error, when available. Note that finding charts for many of the white dwarfs present in this catalog can be found at the following URLs: <pre> <a href="http://procyon.lpl.arizona.edu/WD/charts/">http://procyon.lpl.arizona.edu/WD/charts/</a>; <a href="http://deneb.astro.warwick.ac.uk/phsaap/wdcharts/">http://deneb.astro.warwick.ac.uk/phsaap/wdcharts/</a>; </pre> The second URL contains the finding charts from T.R. Marsh. This is list with about 600 charts. The University of Arizona charts currently have about 2000 charts, but that list is a work in progress with the intent of eventually having all charts available. As discussed in more detail in the HEASARC_Implementation section, this HEASARC representation of the White Dwarf Catalog contains only a subset of the data presented in either the printed version or the version available at the Villanova website, but is intended to be suitable for cross-identification purposes with other catalogs, e.g., of X-ray sources. The original sources for this catalog should always be consulted for the full set of information that is available for these white dwarfs. This database table is based on the Web version of the Villanova White Dwarf Catalog. It was initially created by the HEASARC in May 2003. It is based on the files WD00-07.txt, WD08-15.txt, WD16-23.txt, and WDNewStars.txt obtained from <pre> <a href="ftp://astronomy.villanova.edu/mccook/Current%20Web%20Version%20of%20WD%20Catalog/">ftp://astronomy.villanova.edu/mccook/Current%20Web%20Version%20of%20WD%20Catalog/</a> </pre> It is automatically updated periodically whenever the catalog's authors update these files. This is a service provided by NASA HEASARC .
