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|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first QDOT papers, there have been several hundred velocity changes:some velocities are new, some QDOT velocities have been replaced by moreaccurate values, and some errors have been corrected.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.
|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.
|Large-Scale Structure at Low Galactic Latitude|
We have extended the CfA Redshift Survey to low galactic latitudes toinvestigate the relation between the Great Wall in the North GalacticCap and the Perseus-Pisces chain in the South Galactic Cap. We presentredshifts for 2020 galaxies in the Catalogue of Galaxies and of Clustersof Galaxies (Zwicky et al. 1961-68, CGCG) in the following regions: 4^h^<= α <= 8^h^, 17^h^ <= α <= 20^h^, 0^deg^ <=δ <= 45^deg^. In these regions, the redshift catalogue includes1664 galaxies with B(0) <= 15.5 (of which 820 are newly measured) andis 97% complete. We also include redshifts for an additional 356galaxies in these regions with B(O) > 15.5; of these, 148 werepreviously unmeasured. The CGCG samples the galaxy distribution down tob_II_ = 10^deg^. In this paper, we discuss the acquisition and reductionof the spectra, and we examine the qualitative features of the redshiftdistribution. The Great Wall and the Perseus-Pisces chain are not simplyconnected across the Zone of Avoidance. These structures, which at firstappear to be coherent on scales of ~100 h^-1^ Mpc or more, actually formthe boundaries of neighboring voids of considerably smaller scale,approximately 50h^-1^ Mpc. The structures delineated by ouroptically-selected sample are qualitatively similar to those detected bythe far-infrared-selected IRAS 1.2 Jansky Survey (Fisher et al. 1995).Although the IRAS survey probes more deeply into the Zone of Avoidance,our optically-selected survey provides better sampling of structures atb_II_ >= 10^deg^.
|An image database. II. Catalogue between δ=-30deg and δ=70deg.|
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
|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
|The extended 12 micron galaxy sample|
We have selected an all-sky (absolute value of b greater than or equalto 25 deg) 12 micron flux-limited sample of 893 galaxies from the IRASFaint Source Catalog, Version 2 (FSC-2). We have obtained accurate totalfluxes in the IRAS wavebands by using the ADDSCAN procedure for allobjects with FSC-2 12 micron fluxes greater than 0.15 Jy and increasingflux densities from 12 to 60 microns, and defined the sample by imposinga survey limit of 0.22 Jy on the total 12 micron flux. Its completenessis verified, by means of the classical log N - log S andV/Vmax tests, down to 0.30 Jy, below which we have measuredthe incompleteness down to the survey limit, using the log N - log Splot, for our statistical analysis. We have obtained redshifts (mostlyfrom catalogs) for virtually all (98.4%) the galaxies in the sample.Using existing catalogs of active galaxies, we defined a subsample of118 objects consisting of 53 Seyfert 1s and quasars, 63 Seyfert 2s, andtwo blazars (approximately 13% of the full sample), which is the largestunbiased sample of Seyfert galaxies ever assembled. Since the 12 micronflux has been shown to be about one-fifth of the bolometric flux forSeyfert galaxies and quasars, the subsample of Seyferts (includingquasars and blazars) is complete not only to 0.30 Jy at 12 microns butalso with respect to a bolometric flux limit of approximately 2.0 x10-10 ergs/s/sq cm. The average value of V/Vmaxfor the full sample, corrected for incompleteness at low fluxes, is 0.51+/- 0.04, expected for a complete sample of uniformly distributedgalaxies, while the value for the Seyfert galaxy subsample is 0.46 +/-0.10. We have derived 12 microns and far-infrared luminosity functionsfor the AGNs, as well as for the entire sample. We extracted from oursample a complete subsample of 235 galaxies flux-limited (8.3 Jy) at 60microns. The 60 micron luminosity function computed for this subsampleis in satisfactory agreement with the ones derived from the brightgalaxy sample (BGS) and the deep high-galactic latitude sample, bothselected at 60 microns.
|General study of group membership. II - Determination of nearby groups|
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
|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.
|A study of the large-scale structure in the distribution of galaxies in a region centered about the Cancer cluster. III - Further observational results|
Further observational results are presented from a study of thelarge-scale structure in the distribution of galaxies in anapproximately 4000 sq deg region nominally centered about the Cancercluster. The criteria used in defining the galaxy sample and theobservational methods used in its study are reviewed. The H I spectraand the associated measured parameters and derived properties for the134 sample galaxies are presented.
|Photometry of Zwicky compact galaxies|
The class of Zwicky compact galaxies (ZCGs) with sharp emission lines isshown by the present aperture UBVRI photometry for 80 ZCGs to have thesame color indices as the Markarian galaxies, as well as the bluecompact dwarf and irregular galaxies in the Virgo cluster; it isaccordingly suggested that they define a family, with differences amongindividuals being primarily due to their different star formationactivity status. The ZCGs without emission lines and with U-V greaterthan 0.4 have color indices similar to those of normal ellipticalgalaxies and, consequently, similar stellar contents.
|KISO survey for ultraviolet-excess galaxies. II.|
|Recognition and classification of galaxies with optical jets|
Deep images and spectra are presented for galaxies reported in variouscatalogs to have jets, as well as in a search of the SRC J survey platesin a region near the south galactic pole. Most of these are shown to besuperpositions, polar rings, tidal features, or artifacts of theoriginal plate material. Examples are shown of ten ways that false jetscan be produced, with more detailed case studies for several systems.Based on this experience, several criteria for the brightness, location,and symmetry of genuine optical jets are suggested, which should yieldsurvey samples much less contaminated by 'false alarms' than existingones. Among the objects that remain as optical-jet candidates, ESO0610-23 shows a linear, radial chain of H II regions on the outskirts ofan amorphous system with complex internal structure, UGC 3995 is a closepair of spirals, one of which has a type 2 Seyfert nucleus and apparentknotty jet, and NGC 1598 has the radial features previously reported,but considerable chaotic outer structure as well. Several systems (suchas AM 0207-49 and ESO 2330-38) illustrate the intrinsic difficulty ofseparating jets and tidal tails on morphological grounds alone incertain cases.
|Properties of IRAS galaxies with B(0)T not greater than approximately 14.5|
The optical and infrared properties of 86 galaxies from IRAS circulars1-15, identified with optically bright galaxies in RC-2 and UGC havebeen studied. It is seen that B(0)T, the face-on integratedblue magnitude, is correlated with the far-infrared (FIR) flux. For asubsample of 61 galaxies for which distances are available, it is foundthat the color temperature of FIR emitting dust is correlated with theFIR luminosity, but not with the blue band luminosity. This along withthe observed ratio of L(FIR)/L(B) implies that the observed blueluminosity is unlikely to be associated with young star formationactivity. Associating FIR luminosity with young star formation activityin molecular clouds and the blue luminosity to the mass of the galaxy, avalue of 5-10 solar luminosity/solar mass is estimated for the meanratio of total FIR luminosity to the mass of the gas in these galaxies.
|CO emission from IRAS galaxies|
The results of a search for CO emission in 20 galaxies in the IRAScirculars are presented. The observations were carried out using the14-m millimeter telescope of the Five College Radio AstronomyObservatory (FCRAO) at a half-power beam width of 45 arcsec. CO wasdetected in 10 of the galaxies, including Arp 220 and NGC 6240. A roughcorrelation was found between CO and 10-micron luminosities, although awide scatter was observed in the relation. The very luminous far-IRgalaxies Arp 220 and NGC 6240 contain 3 x 10 to the 10th solar mass ofH2, or a factor of 3 more molecular gas than was found in the luminousspiral galaxies NGC and M51. It is shown that if the far-IR emissionoriginated in a region much smaller than 45 arcsec, the surface densityof the molecular hydrogen in Arp 220 may exceed that observed in any Scgalaxy.
|Far infrared emission from galaxies|
Until recently far infrared (FIR) observations of galaxies were limitedto about a dozen bright and/or active galaxies. New photometric data hasbecome available from Infrared Astronomical Satellite (IRAS) on 33galaxies (most of them faint). The FIR spectra of these galaxies aresimilar. The far infrared flux in the wavelength interval 9-118 micronsof the brighter galaxies is seen to be correlated with the integratedoptical magnitude. The 12 and 25 microns fluxes of these galaxiesexhibit the same dependence on the integrated optical magnitude as the10 and 21 microns fluxes for Seyferts and other emission-line galaxies.This suggests that the galaxies detected by IRAS are some type of activegalaxies in accord with the high percentage of these galaxies predictedby Lock and Rowan-Robinson (1983).
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