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WBLGALAXY - WBL Individual Galaxies Data Catalog (White et al. 1999)

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Overview

The Catalog of Nearby Poor Clusters of Galaxies of White et al. (1999), also known as the WBL Catalog, is a catalog of 732 optically selected, nearby poor clusters of galaxies covering the entire sky north of -3 degrees declination. The poor clusters, called WBL clusters, were identified as concentrations of three or more galaxies with photographic magnitudes brighter than 15.7, possessing a galaxy surface overdensity of 10^(4/3). These criteria are consistent with those used in the identification of the original Yerkes poor clusters, and this new catalog substantially increases the sample size of such objects. These poor clusters cover the entire range of galaxy associations up to and including Abell clusters, systematically including poor and rich galaxy systems spanning over 3 orders of magnitude in the cluster mass function. As a result, this new catalog contains a greater diversity of richness and structures than other group catalogs, such as the Hickson and Yerkes catalogs. This table contains the entries for the individual galaxies in the poor clusters which ere given in Table 3 of the published catalog, and includes redshifts for the individual galaxies and cross-references to other galaxy catalogs. The WBL table (q.v.) contains the entries for the clusters themselves (given in Table 2 of the published catalog).

Catalog Bibcode

1999AJ....118.2014W

References

A catalog of nearby poor clusters of galaxies
       White R.A., Bliton M., Bhavsar S.P., Bornmann P., Burns J.O.,
       Ledlow M.J., Loken C.
      <Astron. J. 118, 2014 (1999)>
      =1999AJ....118.2014W      (SIMBAD/NED BibCode)

Provenance

The WBLGALAXY table was created by the HEASARC in July 2002 based on CDS Catalog J/AJ/118/2014 (the file table3.dat).

Parameters

Name
The WBL Cluster-Galaxy Designation, WBL NNN-GGG, where NNN is the number of the WBL cluster and GGG is a running number in order of increasing RA for the individual galaxy.

RA
The Right Ascension of the WBL cluster member galaxy, taken from the Zwicky Catalog of Galaxies and Clusters of Galaxies (CGCG). This was given in equinox B1950.0 and with a precision of 1 second of time in the published version of the WBL Catalog.

Dec
The Declination of the WBL cluster member galaxy, taken from the Zwicky Catalog of Galaxies and Clusters of Galaxies (CGCG). This was given in equinox B1950.0 and with a precision of 1 arcminute in the published version of the WBL Catalog.

LII
The Galactic Longitude of the WBL cluster member galaxy.

BII
The Galactic Latitude of the WBL cluster member galaxy.

App_Mag
The apparent photographic magnitude, m_pg, of the galaxy taken from the CGCG.

N21_Nearest_Neighbor
A measure of the number of nearest neighbors to the galaxy at the sigma_21 level. This refers to the number of neighbor galaxies falling within the aperture defining the sigma_21 threshold. For a galaxy with no nearest neighbor, the aperture radius is 0.084 degrees at sigma_21. The radius scales as (n + 1)^(1/2), where n is the number of nearest neighbors. For an individual galaxy, the higher the number, the more centrally located it is within the poor cluster. Multiple poor-cluster members with high numbers of neighbors indicate a compact cluster. Galaxies with a nearest neighbor number of zero were merged into a cluster because a nearby galaxy possessed many neighbors. The resulting large aperture [~ (n + 1)^(1/2)] may have overlapped an isolated galaxy in some cases.

N46_Nearest_Neighbor
A measure of the number of nearest neighbors to the galaxy at the sigma_46 level. This refers to the number of neighbor galaxies falling within the aperture defining the sigma_46 threshold. For a galaxy with no nearest neighbor, the aperture radius is 0.057 degrees at sigma_46. The radius scales as (n + 1)^(1/2), where n is the number of nearest neighbors. For an individual galaxy, the higher the number, the more centrally located it is within the poor cluster. Multiple poor-cluster members with high numbers of neighbors indicate a compact cluster. Galaxies with a nearest neighbor number of zero were merged into a cluster because a nearby galaxy possessed many neighbors. The resulting large aperture [~ (n + 1)^(1/2)] may have overlapped an isolated galaxy in some cases.

Subgroup_Flag
A flag which indicates the clustering at the sigma_46 level which gives an indication of the fate of each individual galaxy at the higher density enhancement. A blank field indicates that the galaxy became isolated (no neighbors and no overlapping apertures) and therefore was not considered a member of a cluster at sigma_46. Galaxies with the same letters are part of the same poor cluster at sigma_46. WBL designations for these subgroups should include this letter and indicate that it is a sigma_46 cluster.

Redshift
The redshift of the galaxy reported in NED. Several Zwicky galaxies are actually multiple galaxies and therefore have multiple identifications in NED. In these instances, the average of all redshifts available for the Zwicky galaxy is presented.

Alt_Names
Cross-correlations of the poor cluster galaxy with other galaxy catalogs. Cross identifications for the galaxies are from the NGC (as in Dreyer & Sinnott 1988, NGC 2000.0 Catalog), UGC (Nilson 1973), and IC (as in Dreyer & Sinnott 1988, NGC 2000.0 Catalog) catalogs obtained from NED. For entries that are actually multiple galaxies, all relevant identifications are presented.

Class
The HEASARC Browse object classification: all entries in this table have been given the same generic classification of "galaxy".


Contact Person

Questions regarding the WBLGALAXY database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 8-Nov-2004