A deep optical galaxy search in the southern Milky Way - aimed at reducing
the width of the Zone of Avoidance - revealed 3279 galaxy candidates above the
diameter limit of D > 0.2 arcmin, of which only 112 (3.4%) were previously
catalogued. The surveyed region (266 < l < 296 and -10 < b < +8) lies in the
extension of the Hydra and Antlia clusters - where a supercluster is suspected
- and in the approximate direction of the dipole anisotropy in the Cosmic
Microwave Background radiation. Here we present the optical properties of the
unveiled galaxies such as positions, diameters, magnitudes, morphological
types, including a detailed discussion on the quality of these data and the
completeness limits as a function of the foreground dust extinction. For 127 of
the 227 positional matches in the IRAS PSC, a reliable cross-identification
could be found. Several distinct overdensities and filaments of galaxies can be
identified that are apparently uncorrelated with the Galactic foreground
extinction hence the probable signature of extragalactic large-scale
structures. This catalog constitutes the first part in a series of five equally
conducted optical searches for galaxies in the southern Milky Way (245 < l <
350). With these surveys, the entire Zone of Avoidance will have been covered
by means of visual inspection. The catalogs build the basis for various
spectroscopic and photometric follow-up programs which eventually will allow a
thorough analyse of the galaxy distribution in redshift space and the peculiar
velocity fields within the Zone of Avoidance, as well an an improved
understanding of the Galactic foreground extinction.Comment: Accepted for publication by A&ASS, 50 pages, LaTex, 7 encapsulated
figures, requires aa.cls end epsf.sty. Full-resolution, color figures 1, 2, 6
and 7 are available upon request (E-mail: [email protected]