SNE_ALV (G0): Photographic Supernovae Search Atlas: I,II (19910313)
FILE:
sne_alv1.g0 Volume I: -90 < Dec < -20 (125 galaxies)
sne_alv2.g0 Volume II: -20 < Dec < +20 (711 galaxies)
CONTENTS: Photographic Atlas for Supernovae Search, Volumes I and II
DATASET: These files are part of HyperSky dataset G-8 (G-8.3), version 19910313. Availability on HyperSky CD-ROM: Vol. 1 (1993)
DESCRIPTION: These files are a cross-reference to all galaxies pictured in the two volumes of the Photographic Atlas of Galaxies for Supernovae Search, published by Manuel Lopez Alvarez of Argentina, available in the United States through Willmann-Bell, Inc. File SNE_ALV1.G0 references all galaxies in volume I, and file SNE_ALV2.G0 references all galaxies in volume II.
The purpose of the atlas volumes is to provide supernova hunters with images of southern and equatorial galaxies that are potential producers of supernovae. Each atlas contains photos based on 8-inch f/1.5 Schmidt exposures of individual galaxies and galaxy groups. For some galaxy group photos in Vol 2, Mr. Alvarez has also provided charts which identify the galaxies in the group photo. Thus, these HyperSky files can help the supernova hunter to quickly locate galaxies for which atlas photos exist in equatorial and southern skies.
DATA: The HyperSky files provide the following data for each galaxy. Unless otherwise noted, the data is taken directly from tables in the Alvarez atlas.
POSITION: Because Mr. Alvarez does not give the Right Ascension and Declination to the highest available precision, the positions in these files have been extracted where possible from the NGC 2000 catalog (Roger Sinnott, editor).
MAG: The magnitude given is the integrated apparent blue magnitude of the galaxy, corrected for absorption, following Sandage and Tamman.
TYPE: a brief 2-character code indicating the galaxy type. The first letter in all cases will be 'G' indicating a galaxy. The second letter is coded as follows: 'e'=elliptical; 'i'=irregular; 'a'=amorphous; 's'=spiral.
IDENTIFICATION: the galaxy identification as used on the atlas. Most are NGC (New General Catalog) numbers, but some are IC (Index Catalog) numbers, and a few are from other sources.
COMMENTS: The comments for each galaxy usually include at least two lines. The first line will contain the Hubble classification, as given in the atlas tables. Following this on the same line will be the dimensions of the galaxy. Typically this will take the form Dxd, where D and d are the longest and shortest dimensions. An example would be 3.2x1.1' where the single quote indicates units of minutes of arc.
The second line will contain the atlas page references for the galaxy in the general form "p.AA, BB(3.1.CC)", where AA is the page number of the table entry where useful galaxy information is listed. BB is the page number of the photo of the galaxy. Since there can be several photos on each atlas page, (3.1.CC) will identify the exact photo, where CC is some number. For galaxy groups containing an identifying chart, the chart page number may also be given. Finally, for some galaxies, alternate identifications and abbreviated descriptive comments may appear.