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|Surface photometry of binary galaxies.|
|The Southern Sky Redshift Survey|
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
|A Survey for H 2O Megamasers in Active Galactic Nuclei. I. Observations|
We report an extensive search for 22 GHz H_2_O maser emission fromnearby active galaxies. Our sample includes all Seyfert and LINERgalaxies listed in the Huchra catalog or the Veron-Cetty & Veroncatalog with recessional velocities less than 7000 km s^-1^, and allSeyfert galaxies and LINERs in Huchra's catalog with m_b_ <= 14. Inaddition to these distance- and magnitude-limited samples, we have alsoobserved a number of active galaxies, including radio galaxies, athigher redshift; In all, some 354 galaxies have been surveyed. Ten newH_2_O megamaser sources have been detected, resulting in 16 galaxiesthat are currently known to contain H_2_O masers with isotropicluminosities greater than 20 L_sun_. Of the observed active galaxieswith cz < 7000 km s^-1^, 5.4% have detectable H_2_O megamaseremission. This fraction increases to 11% for those sources with cz <2000 km s^-1^. The newly discovered megamaser sources were monitored onsubsequent observing runs. The strength of the maser features varies forthese sources, as they do for Galactic masers. Three of the galaxieshave sufficient data to test for velocity changes of narrow masercomponents comparable in magnitude to those of the well-studied systemicfeatures in NGC 4258. The maser line in one of these galaxies-NGC2639-is found to have a systematic redward velocity drift of 6.6 +/- 0.4km s^-1^ yr^-1^. No systematic velocity drifts are found for the othertwo sources. We also report large apparent velocity changes in theunusual broad H_2_O emission feature in NGC 1052.
|Candidates for a southern extension of the Karachentsev catalogue of isolated pairs of galaxies.|
|Southern Galaxy Catalogue.|
|Spectroscopic measures of galaxies, their companions, and peculiar galaxies in the southern hemisphere|
Examples of apparent association of galaxies and also of single peculiargalaxies have been drawn from the Catalogue of Southern PeculiarGalaxies and Associations (Arp and Madore, in preparation).Spectroscopic measures are reported for 75 central or peculiar galaxiesand for 97 companion galaxies. Objects are identified by position andillustrated by photographic prints from the UK Schmidt (SRC) survey.Absorption and emission characteristics are tabulated for each spectrum,and heliocentric redshifts are given. The redshifts are calculated to beon the Reference Catalog II system (de Vaucouleurs et al. 1976) towithin plus or minus 50 km/s. The average redshift is repeatable towithin plus or minus 50 km/s. Differential redshifts of objects observedsimultaneously or sequentially can be considerably more accurate.
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