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Table name: abell Records: 5524 Version: 1988 Spectral Band: Uband,Vband,OPT Kind of Object: Cluster of Galaxies Mode: Redshift Preview: No Coordinates: J2000
Name Type Meaning
number C Running number ("Abell" number) in order of right
ascension for 1855 as listed by Abell (1958) for the
northern clusters (1 to 2712) and in order of right
ascension for 1950 for the southern clusters (2713
to 4076). The supplementary southern clusters are
numbered from S1 to S1174.
field C The Southern Sky Survey Field number in which the
cluster is located. For clusters found in two or more
fields, the field given is the one in which the
cluster is closest to the plate center.
r_a I Right Ascension for 1950 of the apparent cluster center.
dec I Declination for 1950 of the apparent cluster center.
atype C Cluster classification in Abell's system:
I = irregular, R = regular, IR and RI = intermediate.
":" indicates a mean type with differences between
estimates of two steps, or an uncertain type estimate;
"?" indicates a mean type with differences between
estimates of three steps, or a questionable type
estimate.
bmtype C Classification in the Bautz-Morgan system
(Bautz and Morgan 1970). ":" indicates a mean type
with differences between estimates of two steps,
or an uncertain type estimate; "?" indicates a mean
type with differences between estimates of three or
more steps, or a questionable type estimate. For the
northern Abell catalogue, these types are primarily
from Leir and van den Bergh (1977). Other sources for
the northern catalogue are Bautz and Morgan (1970),
Bautz(1972), Corwin (1974), Kristian et al (1978),
Sandage et al (1976), and White (1978).
xcen I Rectangular coordinates in millimeters of the apparent
cluster center, refered to the CENTER of the Southern
Sky Survey Field given in the previous column.
ycen I Rectangular coordinates in millimeters of the apparent
cluster
lists C Sources of previous listings (see lists) Even though
all questionable cases of cross identification were
checked on the Southern Sky Survey, there remain a few
uncertain cases. These are given in the Notes to the
Catalogue.
obs C Number of fields in which the cluster was found,
and the observer's initial (A = Abell, C = Corwin,
O=Olowin).
z I Cluster redshift
z_c C Flag for uncertainties on z
m1 I Weighted mean total V magnitude estimate for the
first-ranked cluster member. No galactic extinction
correction has been applied.
m1_c C Flag for uncertainties on m1: ":" indicates a mean
magnitude with a standard deviation of more than
+-0.5 mag, or an uncertain magnitude estimate.
"?" indicates a mean magnitude with a standard
deviation of more than +-1.0 mag, or a questionable
magnitude estimate. *"*" indicates that the
magnitude estimate is for a known or probable
foreground object.
m3 I Weighted mean total V magnitude estimate for the
third-ranked cluster member, again uncorrected for
galactic extinction.
m3_c C Flag for uncertainties on m3 (see m1_c)
m10 I Weighted mean total V magnitude estimate for the
tenth-ranked cluster member, again uncorrected for
galactic extinction.
m10_c C Flag for uncertainties on m10 (see_m1_c)
m10a I Magnitude for the tenth-ranked cluster member in
Abell's (1958) system, corrected for galactic extinction
following Abell's formula. For the northern Abell
catalogue, this is Abell's original magnitude. For the
southern catalogue, these were transformed from the
m10 on the first line (see text).
m10a_c C Flag for uncertainties on m10a (see_m1_c)
xll I Rectangular coordinates of the apparent cluster
center, refered to the south-east (lower left) edge of
the Southern Sky Survey Field given in the first line.
The field edges are defined by the crosses near the
edges of the plates; thus, it is possible for these
coordinates to be negative. For the northern Abell
catalogue, these coordinates are from Rood and
Sastry (1971). Olowin's data were transformed
assuming that the plate center is 164 millimeters from
the crosses.
yll I Rectangular coordinates of the apparent cluster center.
members I Number of cluster members between m3 and m3+2,
corrected for background contamination using the
"universal" luminosity function from Rainey (1976).
The southern counts are corrected to the system of the
northern catalogue (see text).
members C Flag for uncertainties on members
dist I Distance class corresponding to Abell's (1958)
criteria. For the northern Abell catalogue, this is
Abell's original distance class from his m10.
For the southern catalogue, these are from the m10A's
listed in the next column.
rich I Richness class as defined by Abell (1958). For the
northern Abell catalogue, this is Abell's original
richness_class.
r_a F J2000 Right Ascension d_e F J2000 Declination l_ii F Galactic Longitude b_ii F Galactic Latitude L F SuperGalactic Longitude B F SuperGalactic Latitude
The field centers are defined by the crosses near the edges of the plates. The positive x direction is to the east (left) and the positive y direction is to the north (top). These are in the same sense as the rectangular coordinates given by Lauberts (1983) in the ESO/Uppsala Catalogue, and are listed to facilitate location of the cluster on the 5 x 5 degree ESO 1.0-m Schmidt portion of the Southern Sky Survey. Abell and Corwin measured rectangular coordinates from the left and bottom edges of the plates, so the xcen and ycen from their data are calculated assuming that the plate center is 164 millimeters from the left and bottom crosses on the plates (they also measured the crosses). Olowin refered his rectangular coordinates directly to the plate center as defined by the crosses, so no transformation is necessary for his data.
0 : counts 30- 49
1 : counts 50- 79
2 : counts 80-129
3 : counts 130-199
4 : counts 200-299
5 : counts 300 or over
B Braid and MacGillivray (1978) D Duus and Newell (1977) d Dressler (1980) K Klemola (1969) O Olowin (1987) Q Quintana and White (1980 and private communication) R Rose (1976) S Sersic (1974) s Snow (1970)