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|Infrared Observations of Galaxies in the Local Universe. II. 391 Calibrated Images with Photometric and Structural Measurements|
This paper presents empirical results from a deep imaging survey ofgalaxies in the local universe at the J and Ks wavelengths.Three hundred ninety-one images have been obtained and calibrated usingthe same camera and filter set with the Steward Observatory 1.6 m KuiperTelescope on Mount Bigelow and the 2.3 m Bok Telescope on Kitt Peak. Thelimiting magnitude is typically 22 mag arcsec-1 at J and 21mag arcsec-1 at Ks. The central surfacebrightness, apparent magnitudes, sizes, scale lengths, and inclinationsare tabulated from measurements made using these data. The purpose ofthis paper is to provide basic near-infrared data on a variety of galaxytypes.
|The UZC-SSRS2 Group Catalog|
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
|Galaxies with Rows|
The results of a search for galaxies with straight structural elements,usually spiral-arm rows (“rows” in the terminology ofVorontsov-Vel'yaminov), are reported. The list of galaxies that possess(or probably possess) such rows includes about 200 objects, of whichabout 70% are brighter than 14m. On the whole, galaxies with rows makeup 6 8% of all spiral galaxies with well-developed spiral patterns. Mostgalaxies with rows are gas-rich Sbc-Scd spirals. The fraction ofinteracting galaxies among them is appreciably higher than amonggalaxies without rows. Earlier conclusions that, as a rule, the lengthsof rows are similar to their galactocentric distances and that theangles between adjacent rows are concentrated near 120° areconfirmed. It is concluded that the rows must be transient hydrodynamicstructures that develop in normal galaxies.
|The QDOT all-sky IRAS galaxy redshift survey|
We describe the construction of the QDOT survey, which is publiclyavailable from an anonymous FTP account. The catalogue consists ofinfrared properties and redshifts of an all-sky sample of 2387 IRASgalaxies brighter than the IRAS PSC 60-μm completeness limit(S_60>0.6Jy), sparsely sampled at a rate of one-in-six. At |b|>10deg, after removing a small number of Galactic sources, the redshiftcompleteness is better than 98per cent (2086/2127). New redshifts for1401 IRAS sources were obtained to complete the catalogue; themeasurement and reduction of these are described, and the new redshiftstabulated here. We also tabulate all sources at |b|>10 deg with noredshift so far, and sources with conflicting alternative redshiftseither from our own work, or from published velocities. A list of 95ultraluminous galaxies (i.e. with L_60μm>10^12 L_solar) is alsoprovided. Of these, ~20per cent are AGN of some kind; the broad-lineobjects typically show strong Feii emission. Since the publication ofthe first QDOT papers, there have been several hundred velocity changes:some velocities are new, some QDOT velocities have been replaced by moreaccurate values, and some errors have been corrected. We also present anew analysis of the accuracy and linearity of IRAS 60-μm fluxes. Wefind that the flux uncertainties are well described by a combination of0.05-Jy fixed size uncertainty and 8per cent fractional uncertainty.This is not enough to cause the large Malmquist-type errors in the rateof evolution postulated by Fisher et al. We do, however, find marginalevidence for non-linearity in the PSC 60-μm flux scale, in the sensethat faint sources may have fluxes overestimated by about 5per centcompared with bright sources. We update some of the previous scientificanalyses to assess the changes. The main new results are as follows. (1)The luminosity function is very well determined overall but is uncertainby a factor of several at the very highest luminosities(L_60μm>5x10^12L_solar), as this is where the remainingunidentified objects are almost certainly concentrated. (2) Thebest-fitting rate of evolution is somewhat lower than our previousestimate; expressed as pure density evolution with density varying as(1+z)^p, we find p=5.6+/-2.3. Making a rough correction for the possible(but very uncertain) non-linearity of fluxes, we find p=4.5+/-2.3. (3)The dipole amplitude decreases a little, and the implied value of thedensity parameter, assuming that IRAS galaxies trace the mass, isΩ=0.9(+0.45, -0.25). (4) Finally, the estimate of density varianceon large scales changes negligibly, still indicating a significantdiscrepancy from the predictions of simple cold dark matter cosmogonies.
|Arcsecond Positions of UGC Galaxies|
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
|Infrared Observations of Galaxies in the Local Universe. I. The Survey and Some Representative Results|
This paper introduces a continuing survey of galaxies in the localuniverse. Consistent deep images are being acquired for a representativesample of 321 galaxies in the Uppsala General Catalogue down to 21.7 magarcsec-2 at Ks (2.16 mu m) and 22.4 mag arcsec-2 at J (1.25 mu m) usinga NICMOS camera with a 3.'8 x 3.'8 field of view attached to the 61 inch(1.5 m) telescope on Mount Bigelow. We provide some examples of theresults being obtained by employing 64 deep images of a subset of 44galaxies. Bulge-to-disk ratios are tabulated for 30 galaxies. Thebrightness of the central region of 44 galaxies declines approximately 5mag from Hubble type S0 to Sm. An exponential vertical scale height atKs is found to be 500 pc for the disk of UGC 5173. Arm amplitudes offour nearly face-on spiral galaxies are found to range between 11% and88% compared to the interarm region. There is some evidence that the armamplitude is larger at Ks than it is at J. Color gradients are measuredfor 15 galaxies with only one showing a significant nonzero result. Ameasurement of galactic symmetry applied to 64 deep images reveals anaverage asymmetry of 7.6% ( sigma = 4.6%) for these galaxies.
|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.
|The Peculiar Morphology of the Irregular Galaxy NGC 1427A|
Multicolor surface photometry and fragmentary low-resolutionspectroscopy of the irregular galaxy NGC 1427A are presented. Thisgalaxy, a member of the Fornax Cluster, has not been studied in detailpreviously. It shows a very distinctive morphology: a low surfacebrightness stellar background with several bright knots forming adistorted ring-like structure. A faint plume and several diffusedfilaments connect the northern part of the main body of the galaxy withan object having elliptical isophotes. The overall aspect of NGC 1427A,then, resembles that of known interacting galaxies. The very blue colorsof the bright knots show that they are composed by young stars, andseveral of them also show emission lines. The northern object, which hasitself a couple of these blue knots, is bluer than the background of themain body of the galaxy. This fact indicates that the star formationhistories in both objects have been different. Morphologically, thenorthern object is similar to the numerous dwarf elliptical or irregulargalaxies that populate the Fornax Cluster. The possibility of aninteraction being the cause of the particular structure of this galaxyis discussed.
|Large-Scale Structures in the Zone of Avoidance: The Galactic Anticenter Region|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...449..527L&db_key=AST
|Synthetic QSO host galaxies|
The subtraction of a point-spread function (PSF) from quasi-stellarobject (QSO) images and subsequent deconvolution of the residual is atool of potential interest for exploring the properties of QSO hostgalaxies. To test the power of this technique, we synthesize theappearance of QSOs at z = 0.3 by combining bright stellar profiles andartificially redshifted images of seven nearby, luminous galaxies withinteresting morphology. Such models offer an opportunity to measure howwell the profile substraction method is able to recover the flux andstructure of host galaxies. Morphologically, several of our models doresemble real QSOs. In particular, the object created from the image ofArp 243 looks very much like Mrk 1014. Some QSOs have compact galacticcompanions; these systems appear to be well represented by our QSOmodels employing interacting galaxies as hosts. Although, for an assumedseeing full-width at half maximum (FWHM) of 1.1 sec, the subtraction anddeconvolution method successfully recovers characteristic features ofinteracting systems, it is unable to recover spiral structure at thisredshift. Azimuthally averaged radical-brightness profiles of thesubtraction residuals usually match the profiles of the originalgalaxies to within 1.4 sec of the central pixel. For our assumedparameters, careful application of an objective PSF subtractionprocedure can restore an image comprising approximately 90% of a hostgalaxy's total brightness.
|Corrections and additions to the third reference catalogue of bright galaxies|
List of corrections and additions to the Third Reference Catalogue ofBright Galaxies (RC3) are given. The corrected version of the catalogue(RC3.9b), dated April 1994, is currently available through the nationaldata centers.
|A near-infrared imaging survey of interacting galaxies - The small angular-size ARP systems|
Near-IR images of a large sample of interacting galaxies selected fromthe Atlas of Peculiar Galaxies by Arp (1966) have been obtained.Approximately 180 systems have been imaged in at least two, and usuallythree of the standard JHK bands. The survey and the observing and datareduction procedures, are described, and contour plots and aperturephotometry are presented. Future papers will analyze the imaging data bygroupings based on interaction type, stage, and progenitors. The goalsof the analysis are to explore the relationships between galaxyinteractions, activity, and morphology by studying the structure of thenear-IR luminosity distribution, where extinction effects are muchreduced relative to the optical and the major stellar mass component ofgalaxies dominates the observed light.
|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.
|Star formation rates in ring galaxies from IRAS observations|
IRAS and optical data for a sample of 26 ring galaxies are analyzed, andit is found that: (1) relatively high average values of far-infraredluminosity L(FIR), infrared to blue luminosity ratio L(FIR)/L(B), andcolor temperature compared to normal galaxies, implying a high recentstar formation rate; (2) evidence that a large fraction of the youngstars are located in the rings, indicating a very extended, coherentstarburst; and (3) a possible trend of the dispersion of L(FIR) amongrings as a function of ring diameter. Thus, within the uncertaintiesinherent in the study of this relatively small sample, it appears thatring galaxies represent a unique class of nonnuclear coherentstarbursts.
|Colliding and merging galaxies|
The current knowledge of the evolutionary mechanisms of galaxies issummarized, with particular attention given to collisions and mergers.Specific topics discussed include tidal friction, orbital decay, andviolent relaxation; observational evidence for mergers; ripples inellipticals; and S0 galaxies with polar rings. The discussion alsocovers 'cannibalism' in clusters of galaxies, starbursts, and thedelayed formation of elliptical galaxies through mergers of spirals.
|The nuclear activity of interacting galaxies|
A search for active galactic nuclei among interacting galaxies isreported. A sample of 167 systems of interacting and asymmetric galaxieswas observed spectrophotometrically in the spectral range 4700-7100 A.The results are compared with a sample of isolated galaxies. It is foundthat (1) there are no Seyfert nuclei in elliptical or dwarf irregulargalaxies of the sample; (2) there is an excess of Seyfert nuclei amonginteracting spirals, but it is only at the 90 percent confidence level;(3) this excess becomes statistically significant (98 percent) when onlystrongly interacting spirals are included (four new Seyfert nuclei arepresented); (4) in the subgroup of galaxies with extreme tidaldistortions, no Seyfert nuclei were found.
|Infrared observations of interacting/merging galaxies|
The present sample of 20 galaxy systems, selected on the basis ofmorphological evidence for the tidal interaction or merger of twogalaxies and observed at 1-10 microns, is noted to include 11 systems,detected at 10 microns, which have on average a significantly higher IRluminosity than noninteracting galaxies. The enhanced IR radiation isdue to star formation bursts. On the basis of IR Astronomical Satelliteresults for a sample of galaxies, as much as 30 percent of all thefar-IR emission observed arises in bursts of star formation that aretriggered by interactions, and massive stars account for most of theluminosity in these bursts. It is suggested, in view of a massive starformation rate in the interacting and merging galaxies that is about 3times higher than in noninteracting systems, that much of this starformation occurred in either nuclear regions or merger remnants.
|Seven poor clusters of galaxies|
The measurement of 83 new redshifts from galaxies in the region of sevenof the poor clusters of galaxies identified by Morgan et al (1975) andAlbert et al (1977) has been followed by an estimation of cluster massesthrough the application of both the virial theorem and the projected masmethod. For each system, these two estimates are consistent. For the twoclusters with highest X-ray luminosities, the line-of-sight velocitydispersions are about 700 km/sec, while for the five other clusters, thedispersions are of the order of less than about 370 km/sec. The D or cDgalaxy in each poor cluster is at the kinematic center of each system.
|New radial velocities of galaxies from image-tube spectra.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..409K&db_key=AST
|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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