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Extragalactic large-scale structures behind the southern Milky Way. IV. Redshifts obtained with MEFOS
As part of our efforts to unveil extragalactic large-scale structuresbehind the southern Milky Way, we here present redshifts for 764galaxies in the Hydra/Antlia, Crux and Great Attractor region(266o ≤ℓ ≤338o, | b | 10o), obtained with the Meudon-ESO Fibre Object Spectrograph(MEFOS) at the 3.6-m telescope of ESO. The observations are part of aredshift survey of partially obscured galaxies recorded in the course ofa deep optical galaxy search behind the southern Milky Way(Kraan-Korteweg \cite{Kra00a}; Woudt & Kraan-Korteweg \cite{Wou01}).A total of 947 galaxies have been observed, a small percentage of thespectra (N = 109, 11.5%) were contaminated by foreground stars, and 74galaxies (7.8%) were too faint to allow a reliable redshiftdetermination. With MEFOS we obtained spectra down to the faintestgalaxies of our optical galaxy survey, and hence probe large-scalestructures out to larger distances (v 30 000 km s-1)than our other redshift follow-ups using the 1.9-m telescope at theSouth African Astronomical Observatory (Kraan-Korteweg et al.\cite{Kra95}; Fairall et al. \cite{Fai98}; Woudt et al. \cite{Wou99})and the 64-m Parkes radio telescope (Kraan-Korteweg et al.\cite{Kra02}). The most distinct large-scale structures revealed in thesouthern Zone of Avoidance are discussed in context to known structuresadjacent to the Milky Way.Tables 1 and 2 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/415/9 Based onobservations taken at the European Southern Observatory, La Silla,Chile.
| A catalog of galaxies behind the Southern Milky Way . I. The Hydra/Antlia extension (l~ 266or - 296or)
A deep optical galaxy search in the southern Milky Way - aimed atreducing the width of the Zone of Avoidance - revealed 3279 galaxycandidates above the diameter limit of D >~ 0.2', of which only 112(3.4%) were previously catalogued. The surveyed region (266o<~ \ell <~ 296o and -10o <~ b <~+8o) lies in the extension of the Hydra and Antlia clusters -where a supercluster is suspected - and in the approximate direction ofthe dipole anisotropy in the Cosmic Microwave Background radiation. Herewe present the optical properties of the unveiled galaxies such aspositions, diameters, magnitudes, morphological types, including adetailed discussion on the quality of these data and the completenesslimits as a function of the foreground dust extinction. For 127 of the227 positional matches in the IRAS PSC, a reliable cross-identificationcould be found. Several distinct overdensities and filaments of galaxiescan be identified that are apparently uncorrelated with the Galacticforeground extinction hence the probable signature of extragalacticlarge-scale structures. This catalog constitutes the first part in aseries of five equally conducted optical searches for galaxies in thesouthern Milky Way (245o <~ \ell <~ 350o).With these surveys, the entire Zone of Avoidance will have been coveredby means of visual inspection. The catalogs build the basis for variousspectroscopic and photometric follow-up programs which eventually willallow a thorough analyse of the galaxy distribution in redshift spaceand the peculiar velocity fields within the Zone of Avoidance, as wellan an improved understanding of the Galactic foreground extinction.Tables 1 and 2 are available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Core properties of elliptical galaxies - I. A northern hemisphere sample at high resolution
We introduce an ongoing survey of core properties of elliptical galaxiesand present the first results from high-resolution direct imaging of asubsample. The data were obtained in the V, R and I bands at the NOTtelescope, with median seeings of 0.69, 0.65 and 0.62 arcsec FWHM,respectively. We determine the `classical' core parameters, and weintroduce a new parameter, pi_c, which is a measure of the deviation ofthe observed brightness profile from an isothermal profile, pi_cmeasures the intensity of a central brightness concentration in excessof an isothermal model, relative to the intensity of the core. Measuringpi_c for the objects presented here, we find that only five of 22objects are consistent with pi_c=0 at the 1sigma level, and that 14 of22 are inconsistent with pi_c at the 3sigma level. We see no evidencefor significant colour difference (in V, R and I) between the centralspike and the rest of the core, except for M87 and NGC 4278. For theremaining galaxies we find that the colours of the spike must matchthose of the core to within 0.4 mag. We conclude that the majority ofall ellipticals seem to have central intensity concentrations in therange 1-10 per cent of the core flux.
| Southern Galaxy Catalogue.
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