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6. The catalogue

The catalogue, available in electronic form alone at the CDS (Centre de Données Astronomiques de Strasbourg), presents the following entries for all objects in both regions of observation (the large central zone and the smaller south-west area - see Fig. 1 (click here)):
(1, 2, 3) Right ascension (1950).
(4, 5, 6) Declination (1950).
(7) Isophotal radius tex2html_wrap_inline1064 in arcsec.
(8) Central surface brightness tex2html_wrap_inline1066 in tex2html_wrap_inline1068.
(9) Isophotal apparent magnitude tex2html_wrap_inline1070.
(10) Magnitude error (in modulus), as estimated by Eq. (2 (click here)).
(11) Classification of the object: tex2html_wrap_inline1072 star, tex2html_wrap_inline1074 galaxy.
(12) GMP number, when available. The letter after the number indicates the GMP catalogue used for the matching: g stands for the GMP (1983) galaxy catalogue, while s stands for the GMP unpublished star catalogue. The correspondance was obtained by cross-correlating positions. Do notice there are inevitable ambiguities in this cross-identification, possibly due to non resolution of close objects by GMP or simply to confusion when several close neighbours exist. That is why there are 4 entries doubled (because each one of those 4 objects was identified with 2 different GMP objects: 3325g, 3336g, 2976g, 2980g, 4068g, 4075g and 4032s, 4042s). In addition, there are also several other entries which are attributed the same GMP number. We thus caution the reader/potential user of this catalogue to beware not to use these data directly without taking into account this information.
(13, 14) GMP (tex2html_wrap_inline1076) coordinates in arcsec (after slight correction to match GSC positions, as described in Sect. 5 (click here)).
(15) Heliocentric radial velocity in km stex2html_wrap_inline1078, when available, as given by Biviano et al. (1995).

Some of the results derived from the analysis of this catalogue are discussed in Lobo et al. 1996 (in press), Gerbal et al. 1996 (submitted) and the corresponding available spectral data is published by Biviano et al. (1995).


We thank Stéphane Arnouts, Isabel Márquez, Cláudia Mendes de Oliveira and Christopher Willmer for useful discussions on photometry; Francois Sèvre, José Donas and Roland den Hartog for astrometric discussions, and also J.G. Godwin, N. Metcalfe & J.V. Peach for providing us with their unpublished catalogue of stellar objects in the Coma field. We would also like to thank the referee, G. Gavazzi, for helpful comments on the text. We acknowledge financial support from GDR Cosmologie, CNRS; CL is fully supported by the BD/2772/93RM grant attributed by JNICT, Portugal.

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