J/AJ/118/2014 Nearby poor clusters of galaxies catalog (White+, 1999)
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)
ADC_Keywords: Clusters, galaxy ; Galaxy catalogs ; Redshifts ; Cross identifications Keywords: catalogs - galaxies: clusters: general Abstract: A catalog of 732 optically selected, nearby poor clusters of galaxies covering the entire sky north of -3° declination is presented. 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 104/3. 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. The information on individual galaxies includes redshifts and cross-references to other galaxy catalogs. The entries for the clusters include redshift (where available) and cross-references to other group and cluster catalogs. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 112 732 Poor-cluster catalog table3.dat 90 3324 Poor-cluster galaxies table4.dat 19 219 Previous Nomenclature
See also: VII/26 : Uppsala General Catalogue of Galaxies (UGC) (Nilson 1973) VII/49 : Galaxies and Clusters of Galaxies (CGCG) (Zwicky, 1968) VII/118 : NGC 2000.0 (Sky Publishing, ed. Sinnott 1988) VII/190 : Zwicky Galaxy Catalog (Zwicky+ 1968) VII/193 : The CfA Redshift Catalogue, Version June 1995 (Huchra+ 1995) VII/213 : Hickson's Compact groups of Galaxies (Hickson+ 1982-1994) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 7 A7 --- WBL WBL cluster designation (WBL NNN) 9- 10 I2 h RAh Cluster centroid right ascension (B1950.0) 11- 14 F4.1 min RAm Cluster centroid right ascension (B1950.0) 15 A1 --- DE- Cluster centroid declination sign (B1950.0) 16- 17 I2 deg DEd Cluster centroid declination (B1950.0) 18- 19 I2 arcmin DEm Cluster centroid declination (B1950.0) 21- 23 I3 --- Rich Richness (number of CGCG galaxies in each poor cluster) 25- 43 A19 --- Clust. Clustering at σ_46_ (1) 45- 51 F7.5 --- z ? Poor-cluster redshift (2) 53- 55 I3 --- o_z ? Number of galaxy redshifts available from NED 57- 59 A3 --- n_z Notes on z (3) 61- 71 A11 --- ZWCL Zwicky cluster containing the given WBL cluster within its contours 72- 73 A2 --- n_ZWCL [MD ] MD: medium-distant cluster 75- 77 I3 arcmin RZ ? Radius of the Zwicky cluster 79- 82 F4.2 --- fZ ? Distance separating the center of the Zwicky and WBL clusters, in units of the Zwicky cluster radius (4) 84- 87 I4 --- ACO ? Abell cluster cross-correlation (5) 89- 91 I3 --- CfA ? CfA (<VII/193>) group cross-correlation (6) 93- 95 I3 --- HCG ? HCG (<VII/213>) cross-correlation (7) 98-112 A15 --- Yerkes Yerkes cluster cross-correlation (8)
Note (1): An indication of the fate of each individual galaxy at the higher density enhancement (σ46). A single zero in this column indicates that a group at σ21 fractured into single galaxies at σ46 (i.e., the galaxy apertures did not overlap). Combinations of other numbers indicate how many galaxies were in each subcluster at σ46, with "0" indicating one or more isolated galaxies. For example, a cluster with 11 members and an 8+0 in this column becomes a group of eight members with three isolated galaxies at σ46. A cluster of 11 members and an entry of 4+3+2+0 breaks up into three subclusters of four, three, and two members, with two isolated galaxies at σ46. Note (2): Redshift for the cluster, when available, computed as an average of redshifts from the literature obtained through the NASA Extragalactic Database (NED). Note (3): If there is no note, the number of galaxy redshifts were used to compute the cluster redshift. i: there were only two redshifts available and their values differed by more than 1500km/s. n this case, the two galaxies may be close only in projection. The redshift given in this case is the average of the two galaxy redshifts. ii: Of the three or more redshifts available, one was more than 1500km/s from the mean. After removing this discrepant redshift, a new mean was calculated, with all remaining redshifts within 1500km/s from this new mean. iii: Of the three or more redshifts available, at least two discrepant redshifts were present. The redshift listed is then the mean redshift calculated after removing only the most discrepant velocity. A value of 1500km/s was chosen for the cutoff velocity because a "typical" poor cluster has a velocity dispersion of ∼500km/s. This criteria is thus analogous to the standard 3σ lipping often used in the literature. Note (4): The radius is that given in the CGCG and is meant to indicate the area on the sky contained within the hand-drawn contours. Zwicky clusters are rarely spherical, so all correlations were verified by eye. Zwicky clusters are also separated into estimated distance classes, with near clusters meant to be in the redshift range 0.0<z≤0.05 and medium-distant clusters in the range 0.05<z≤0.1 (CGCG). We included any near or medium-distant Zwicky cluster that contained a WBL cluster within its contours. Near clusters were chosen over medium-distant clusters in the very few cases where a poor cluster fell within the boundaries of two Zwicky clusters of different distance classes. Note (5): Any WBL cluster located within one corrected Abell radius of a distance class 3 or nearer Abell cluster was considered associated with the Abell cluster. In addition, NED was used to search for WBL cluster members that were also members of Abell clusters. Note (6): Associated CfA groups were identified as groups whose coordinates were within 30' of the WBL centroid. Note (7): Associated Hickson compact groups were identified from information on individual galaxies obtained through NED. Note (8): The identification of WBL clusters associated with the Yerkes clusters (AWM (Albert et al., 1977ApJ...211..309A, MKW (Morgan et al., 1975ApJ...199..545M) and WP (White, 1978ApJ...226..591W)) was determined visually as a part of the development of the WBL catalog.
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 7 A7 --- WBL WBL cluster designation (WBL NNN) 8- 11 A4 --- gal [-0-9] Galaxy designation in WBL NNN (-NNN) 13- 14 I2 h RAh Right ascension (B1950.0) (1) 16- 17 I2 min RAm Right ascension (B1950.0) 19- 20 I2 s RAs Right ascension (B1950.0) 22 A1 --- DE- Declination sign (B1950.0) 23- 24 I2 deg DEd Declination (B1950.0) 26- 27 I2 arcmin DEm Declination (B1950.0) 29- 32 F4.1 mag Pmag Galaxy apparent photographic magnitude (1) 34- 36 I3 --- N21 ? Nearest neighbors (2) 38- 39 I2 --- N46 Nearest neighbors (2) 41 A1 --- Clust. Clustering atσ_46_ (3) 43- 49 F7.5 --- z ? Redshift of the galaxy reported in NED (4) 51- 90 A40 --- Names Galaxy catalog cross-correlations (5)
Note (1): Data from the CGCG (Cat. VII/49) Note (2): Measure of the number of nearest neighbors to the galaxy at σ21 (N21) and σ46 (N46). This refers to the number of neighbor galaxies falling within the aperture defining the σ21 or σ46 threshold. For a galaxy with no nearest neighbor, the aperture radius is 0.084° at σ21 and 0.057° at σ46. 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. Note (3): 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 σ46. Galaxies with the same letters are part of the same poor cluster at σ46. WBL designations for these subgroups should include this letter and indicate that it is a σ46 cluster. Note (4): 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. Note (5): Cross identifications for the galaxies from the NGC, IC (See Cat. VII/118) and UGC (Cat. VII/26) catalogs obtained from NED. For entries that are actually multiple galaxies, all relevant identifications are presented.
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Name Identification (1) 10- 16 A7 --- WBL WBL designation 18- 19 A2 --- Note [abc ] Note when no WBL poor cluster associated with a Yerkes cluster (2)
Note (1): This table cross-references the names of the poor clusters presented here with previous names used in the literature. We also present a direct comparison of the WBL clusters with the Yerkes (AWM (Albert et al., 1977ApJ...211..309A, MKW (Morgan et al., 1975ApJ...199..545M) and WP (White, 1978ApJ...226..591W)) poor clusters. We list every Yerkes poor cluster along with any corresponding WBL cluster. Note (2): a: Cluster galaxies were too faint to be included in the WBL catalog. b: Cluster is too diffuse to meet the galaxy density criterion of the WBL catalog. c: Cluster is south of -3° declination and therefore not included in the WBL catalog.
History: From AJ electronic version
(End) James Marcout, Patricia Bauer [CDS] 10-Jan-2000
|The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line|