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Redshift-Distance Survey of Early-Type Galaxies: Spectroscopic Data
We present central velocity dispersions and Mg2 line indicesfor an all-sky sample of ~1178 elliptical and S0 galaxies, of which 984had no previous measures. This sample contains the largest set ofhomogeneous spectroscopic data for a uniform sample of ellipticalgalaxies in the nearby universe. These galaxies were observed as part ofthe ENEAR project, designed to study the peculiar motions and internalproperties of the local early-type galaxies. Using 523 repeatedobservations of 317 galaxies obtained during different runs, the dataare brought to a common zero point. These multiple observations, takenduring the many runs and different instrumental setups employed for thisproject, are used to derive statistical corrections to the data and arefound to be relatively small, typically <~5% of the velocitydispersion and 0.01 mag in the Mg2 line strength. Typicalerrors are about 8% in velocity dispersion and 0.01 mag inMg2, in good agreement with values published elsewhere.
| Nearby Optical Galaxies: Selection of the Sample and Identification of Groups
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
| Accurate Positions for MCG Galaxies
We have measured accurate celestial coordinates for 4741 extragalacticobjects, primarily drawn from a list of MCG galaxies with no recentlypublished accurate positions. The standard deviations in the newpositions depend slightly on the measurement method but are on the orderof 1.0" to 1.2". Standard deviations in the original MCG positions areconfirmed to be at the 1.5′-2.0′ level. These new positionswere integrated into NED in 1997 December.
| 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.
| Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies
We present a catalogue of aperture photometry of galaxies, in UBVRI,assembled from three different origins: (i) an update of the catalogueof Buta et al. (1995) (ii) published photometric profiles and (iii)aperture photometry performed on CCD images. We explored different setsof growth curves to fit these data: (i) The Sersic law, (ii) The net ofgrowth curves used for the preparation of the RC3 and (iii) A linearinterpolation between the de Vaucouleurs (r(1/4) ) and exponential laws.Finally we adopted the latter solution. Fitting these growth curves, wederive (1) the total magnitude, (2) the effective radius, (3) the colourindices and (4) gradients and (5) the photometric type of 5169 galaxies.The photometric type is defined to statistically match the revisedmorphologic type and parametrizes the shape of the growth curve. It iscoded from -9, for very concentrated galaxies, to +10, for diffusegalaxies. Based in part on observations collected at the Haute-ProvenceObservatory.
| UBVRI photoelectric photometry of bright southern early-type galaxies
UBVRI multi-aperture photometry of 207 bright southern galaxies and of72 objects of an additional list is presented. These observations weremade for obtaining the magnitude scale zero-point as an accuratedetermination of the sky background for a two-dimensional photometryprogram concerning these galaxies. We have also inferred the asymptoticmagnitudes, color indices and effective apertures of these objects. Ourresults are in good agreement with those of others authors.
| CO observations of Arp's interacting galaxies
We performed a (C-12)O (J= 1-0) line survey involving fifty fourinteracting galaxies from the Arp's Catalogue of Peculiar Galaxies, andcompared our results with various other data. The far infraredluminosities, as normalized by the CO luminosities, are much greater forinteracting galaxies than for normal galaxies. From correlations withthe interaction class we found that the molecular gas concentration inthe central few kpc is not necessarily enhanced by interaction. However,the efficiency of star formation from the molecular gas increasessignificantly with the interaction class, which results in an apparentincrease in the star-formation rate with the interaction class.
| Optical and radio morphology of elliptical dust-lane galaxies - Comparison between CCD images and VLA maps
Optical CCD observations and 20 cm radio continuum observations arepresented for, a sample of 26 hitherto unobserved elliptical galaxieswith strong dust lanes. 21 objects were found to be radio emitters. Highresolution VLA maps of the radio morphology are compared with the dustmorphology. In one case a radio jet was discovered, it is orthogonal tothe dust lane. A careful check of the literature data of all dust-laneellipticals with radio jets shows a strong preference of the jets to beorthogonal to the dust lanes. This has implications for the coupling ofthe angular momentum of the dust lane to the accretion disk and to theblack hole.
| Effects of Interactions on the Radio Properties of Non-Seyfert Galaxies
On the basis of radio surveys published in the literature we havecompared the radio properties of samples of relatively isolated spiralgalaxies with LINER- and H II- region-like nuclei (hereafter called Land H galaxies) with corresponding samples of non-Seyfert interactinggalaxies, in order to explore the effects of interactions on their radioproperties. Basically, we have found enhanced total and central radioemission (per light unit) in interacting H galaxies (compared with theirrelatively isolated counterparts) and enhanced central radio emission(per light unit) in interacting L galaxies. Analogous enhancements inthe strength of the total and nuclear Hα emission lines areobserved in interacting galaxies. Furthermore, within a sample ofinteracting galaxies, there appears to be evidence of enhanced total andcentral radio emission (per light unit) in strongly interacting galaxieswhich are likely to have H II-region-like nuclei, compared withmoderately interacting objects of the same nuclear type. Interacting Hgalaxies contain more extended central radio sources than isolatedgalaxies, whereas no difference in this sense is observed in the case ofL galaxies. L galaxies which contain, on average, weaker total andcentral radio sources than the H galaxies have, on average, smallercentral radio sources (of greater radio surface brightness) than the Hgalaxies and follow a less-steep logarithmic radio power-radio sizerelation. As regards the Seyfert galaxies, which are known to becharacterized by powerful central radio emission, we have found thatthey contain, on average, central radio sources of intermediate size,which obey a power-size relation of intermediate steepness (with respectto the L and H galaxies). Thus our statistical study reveals basicstructural differences between the radio properties of the L, H andSeyfert galaxies, and between the effects of interactions on the radioproperties of the three classes of galaxies.
| A search for megamaser galaxies
The results of a search for OH megamaser emission from a sample of 32galaxies selected from the IRAS Point Source Catalog on the basis oftheir IR properties are presented. For each galaxy (other than those fewalready observed elsewhere), an optical redshift is obtained and both OHand H I emission are sought. The search yielded one new OH megamasergalaxy, and H I was detected toward nine objects. There are unlikely tobe any OH megamasers in the Southern Hemisphere with flux densitiescomparable to that of Arp 220 (280 mJy), although there may be apopulation of weaker megamasers. No special conditions are required toexplain the known OH megamasers other than those expected in a cool,dusty, active galaxy.
| Revised supernova rates in Shapley-Ames galaxies
Observations of 855 Shapley Ames galaxies made from November 1, 1980 toOctober 31, 1988, together with improved supernova luminosities, havebeen used to derive the frequency of supernovae of different types, andthe results are presented in tables. From a uniform database of 24supernovae discovered, the following SN rates are found, expressed in SNper century per 10 to the 10th L(B)(solar): SN Ia, 0.3; SN Ib, 0.3; andSN II, 1.0. The present data confirm the relatively high frequency of SNII in late-type galaxies that has been found by many previousinvestigators.
| The supernova rate in Shapley-Ames galaxies
A visual search for SNs in 748 Shapley-Ames galaxies during the 5-yearperiod from November 1, 1980 to October 31, 1985 has yielded SN rates of0.3h-squared, 0.4h-squared, and 1.1h-squared for objects of types Ia,Ib, and II, respectively. These data are judged to imply that Tammann's(1974, 1982) SN rates are probably too high by a factor of about 3. Fora Galactic luminosity of 2 x 10 to the 10th solar L(B), the predicted SNrates in the Milky Way system are 0.6h-squared, 0.8h-squared, and2.2h-squared/century, respectively, for the three aforementioned types.
| The effects of interactions on spiral galaxies. III - A radio continuum survey of galactic nuclei at 1.49 GHz
The radio continuum emission from the central region of a sample ofinteracting spiral galaxies (92 galaxies of which 60 in a completesample) and of a control sample of more isolated spiral galaxies (94)was observed with the Very Large Array at 1.49 GHz. The angularresolution of the observations is about 1.3 arcsec, and the detectionlimits are about 0.6 and 1.5 mJy for point sources and extended sourceswith a half power size of 10 arcsec, respectively. This survey, incombination with published optical spectroscopy, provides the data for adetailed comparison of the central region in interacting and moreisolated spiral galaxies.
| H I observations of galaxies in between the Local and the Hydra/Centaurus superclusters
H I observations obtained with the 300-ft NRAO and 100-m Effelsbergradio telescopes in 1984-1985 are reported for 440 galaxies, ofmorphological types S0/a or later and diameter at least 2 arcmin in thecatalog of de Vaucouleurs et al., 1976, from the region between theLocal and Hya/Cen superclusters. The data are compiled in tables alongwith published data on 310 galaxies to form a data base for studies offilamentary structures in the intercluster region. More than 50 percentof the galaxies are detected in H I, and the redshift distribution isfound to be consistent with the existence of filaments.
| Die elliptischen Staubstreifen-Galaxien NGC 5266 und NGC 4933
Not Available
| The effects of interactions on spiral galaxies. I - Nuclear activity and star formation
When the present results of spectrophotometry for the nuclei of 161(mostly spiral) galaxies with bright companions and emission lineimaging of 63 galaxies were compared to a similarly observed sample ofisolated-spiral nuclei, both samples of interacting galaxies exhibitedsignificant excesses of nuclear emission. The rate of nuclear starformation is significantly above average even in systems withoutnoticeable tidal distortion in the outer disks, suggesting that thenear-nuclear gas is only marginally stable in isolated galaxies. Theresults obtained suggest that nuclear phenomena are triggered by atidally induced influx of gas from the disk into the nuclear regions,rather than gas transfer between the galaxies.
| Atlas of Peculiar Galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966ApJS...14....1A&db_key=AST
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