VII/159 Catalogue of galaxies towards the Coma Supercluster (Slezak+ 1988)
Study of a field in the Coma Supercluster. I. Automated galaxies count
Slezak E., Mars G., Bijaoui A., Balkowski C., Fontanelli P.
<Astron. Astrophys. Suppl. Ser. 74, 83 (1988)>
=1988A&AS...74...83S 1988A&AS...74...83S
ADC_Keywords: Clusters, galaxy ;
Keywords: Coma Supercluster - image processing in astronomy - galaxy count -
Schmidt plate analysis
Description: (Summary of the paper)
The existence of a filament of galaxies was shown by Fontanelli
(1984) in the Coma cluster region. This paper concerns the study of
a IIIaJ Palomar Schmidt plate of the Eastern end of this filament.
We have developed a real time reduction technique, quite similar to
that used for the COSMOS machine and performed, in real time, an
image segmentation. The galaxy selection was made using a classical
Bayesian classification based on the diagram of the integrated
density versus the area. All the non-stellar objects were thus
identified using the PDS and a morphological type was attributed
to the galaxies. Our catalogue gives coordinates, magnitudes
(derived from the Zwicky et al. (1961-68) and Nilson (1973)
catalogues), area in pixels, and morphological types for 7582
galaxies. A histogram of all the galaxy magnitudes shows that the
catalogue is apparently complete down to about the 19th magnitude.
The asymmetry in the distribution of the bright objects between the
North-West and the South-East part of the plate found by Fontanelli
(1984) is also present for the fainter objects of our catalogue. We
have identified galaxy condensations using an image segmentation on
the galaxy density map. The parameters, position, axis, and
orientation of these condensations have been estimated.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog 64 7582 *Galaxies towards the Coma Supercluster
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Note on catalog: only the 1199 galaxies brighter than 18.0
(i.e. with a non-zero number in the first column) are
published in the Table 1 of the paper.
The column "Area in pixels" is not recorded here.
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Byte-per-byte Description of file: catalog
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Bytes Format Unit Label Explanation
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1- 5 I5 --- NmB18 [0,1199]?=0 Object number for the galaxies
brighter than the 18th magnitude
(otherwise 0).
7- 11 I5 --- N [1,7582]+ Object number
15- 16 I2 h RAh [13] right ascension (hours) (J2000)
18- 19 I2 min RAm [13,42]+= right ascension (minutes)
21- 25 F5.2 s RAs [0,60.0] right ascension (seconds)
28 A1 --- DE- [ ] declination sign
29- 30 I2 deg DEd declination (degrees) (J2000)
32- 33 I2 arcmin DEm declination (minutes)
35- 39 F5.2 arcsec DEs declination (seconds)
44- 49 F6.3 mag Bmag B magnitude
52- 62 A11 --- MType morphological type
63- 64 A2 --- Note [ *v] SIMBAD or velocity note (1)
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Note (1): the symbol is:
'*' = object with identification in SIMBAD (Strasbourg Data Center).
'v' = object with a known radial velocity.
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History:
The catalogue was provided by courtesy of E. Slezak to H. Andernach;
it was numbered A100 in H. Andernach's "List of Astronomical Catalogues
and Documents kindly provided on request by various authors"
01-Oct-1993: First archived.
12-Jan-1994: "Intro" file has been slightly rewritten.
(The date of the latest archive, see the date of each file.)
08-Aug-1997: this documentation has been standardized at CDS
(Francois Ochsenbein)
References:
Zwicky, F., Herzog, E., Wild, P., Karpowicz, M., and Kowal C.T. 1961-68,
Catalogue of Galaxies and of Clusters of Galaxies, I-VI (Pasadena,
California Institute of Technology) (catalogs VII/4, VII/190)
Nilson, P. 1973, Uppsala Ann. 6 (catalog VII/26)
Fontanelli, P. 1984A&A...138...85F 1984A&A...138...85F
Slezak E., Bijaoui A., Mars G., 1988A&A...201....9S 1988A&A...201....9S (Paper II)
(End) Koichi Nakajima [CDS] 27-Sep-1993