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Kinematics of the Local Universe. XIII. 21-cm line measurements of 452 galaxies with the Nançay radiotelescope, JHK Tully-Fisher relation, and preliminary maps of the peculiar velocity field
Aims.This paper presents 452 new 21-cm neutral hydrogen linemeasurements carried out with the FORT receiver of the meridian transitNançay radiotelescope (NRT) in the period April 2003-March 2005. Methods: This observational programme is part of a larger projectaiming at an exhaustive and magnitude-complete HI extragalacticcatalogue for Tully-Fisher applications (the so-called KLUN project, forKinematics of the Local Universe studies, to end in 2008). The wholeon-line HI archive of the NRT today contains reduced HI-profiles for4500 spiral galaxies of declination δ > -40°(http://klun.obs-nancay.fr). Results: As an example of thisapplication, we used the direct Tully-Fisher relation in three (JHK)bands in deriving distances to a large catalogue of 3126 spiral galaxiesdistributed through the whole sky and sampling the radial velocity rangewell between 0 and 8000 km s-1. Thanks to an iterative methodaccounting for selection bias and smoothing effects, we show a detailedand original map of the velocity field in the Local Universe as apreliminary output.Data Tables [see full text], [see full text], and [see full text]and HI-profiles (Fig. [see full text]) are only available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/465/71
| A Digital Archive of H I 21 Centimeter Line Spectra of Optically Targeted Galaxies
We present a homogeneous compilation of H I spectral parametersextracted from global 21 cm line spectra for some 9000 galaxies in thelocal universe (heliocentric velocity-200
| The 2MASS-selected Flat Galaxy Catalog
An all-sky catalog of 18020 disc-like galaxies is presented. Thegalaxies are selected from the Extended Source Catalog of the Two MicronAll-Sky Survey (XSC 2MASS) basing on their 2MASS axial ratio a/b ≥ 3.The Catalog contains data on magnitudes of a galaxy in the J, H,KS bands, its axial ratio, positional angle, index ofluminosity concentration, as well as identification of the galaxy withthe LEDA and the NED databases. Unlike the available optical catalogs,the new 2MFGC catalog seems to be more suitable to study cosmicstreaming on a scale of z <~ 0.1. The dipole moment of distributionof the bright (K < 11m) 2MFGC objects (l = 227°, b =41° or SGL = 90°, SGB = -43°) lies within statistical errors(±15°) in the direction of the IRAS dipole and the opticalRFGC dipole.
| Observing the Dark Matter Density Profile of Isolated Galaxies
Using the Sloan Digital Sky Survey (SDSS), we probe the halo massdistribution by studying the velocities of satellites orbiting isolatedgalaxies. In a subsample that covers 2500 deg2 on the sky, wedetect about 3000 satellites with absolute blue magnitudes going down toMB=-14; most of the satellites have MB=-16 to -18,comparable to the magnitudes of M32 and the Magellanic Clouds. After acareful, model-independent removal of interlopers, we find that theline-of-sight velocity dispersion of satellites declines with distanceto the primary. For an L* galaxy the rms line-of-sightvelocity changes from ~120 km s-1 at 20 kpc to ~60 kms-1 at 350 kpc. This decline agrees remarkably well withtheoretical expectations, as all modern cosmological models predict thatthe density of dark matter in the peripheral parts of galaxies declinesas ρDM~r-3. Thus, for the first time we finddirect observational evidence of the density decline predicted bycosmological models; we also note that this result contradictsalternative theories of gravity such as modified Newtonian dynamics(MOND). We also find that the velocity dispersion of satellites within100 kpc scales with the absolute magnitude of the central galaxy asσ~L0.3 this is very close to the Tully-Fisher relationfor normal spiral galaxies.
| 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.
| Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
| 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.
| 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.
| Radio Properties and Optical Identification of Two Samples of Millijansky Radio Sources at 1.4 GHz
From the 1.4 GHz radio survey of Condon, Dickey, & Salpeter in aregion much devoid of rich galaxy clusters at redshifts z <~ 0.4, weselected a "distant" sample of 57 radio sources complete to a 1.4 GHzflux density of 35 mJy and a "nearby" sample of 36 mostly weaker radiosources which are optically brighter than B~19 mag. Our ultimate goalsare (1) to study the radio, optical, and near-IR properties of thosehigh-redshift (z~1), moderate-power radio sources in the distant sampleand to compare them with that of more powerful radio sources, and (2) tomake a comparison of primarily noncluster radio sources in the nearbysample with a companion survey of radio sources in a pair of richsuperclusters at z ~ 0.1. In this first paper of a series, we report ournew C-array VLA continuum snapshots at 4.86 GHz and optical R-band CCDimaging photometry for these two samples and tabulate the observationalresults on individual sources. Some direct sample statistical propertiesare also discussed in the paper and summarized as follows: (l) Thedistant sample: (a) the sample median flux density at 1.4 GHz is about65 mJy. (b) The majority (80%) of the sample sources have a steepspectrum between 1.4 and 4.86 GHz with a spectral index around 0.9.Nineteen (90%) of the 21 sources that are fully resolved at 4.86 GHz(i.e., angular sizes θ >~ 11") have a radio morphology ofFanaroff-Riley (FR) II type. (c) Thirty-seven (88%) of the 42 opticallyimaged sample sources were optically identified to a limiting R-bandmagnitude of R ~ 23.5 mag. About 15% of the identified radio sourcesappear to be point sources, and the others are extended galaxies with anappearance similar to nearby elliptical galaxies. (d) Twenty-eight (76%)of the optically identified sources have R > 20 mag, suggesting thatthese are probably distant (z> 0.8), with a redshift distributionpeaking at z ~ 1, where their radio luminosities are about 10 times thebreak power between the FR I and II classes. (e) We found no strongevidence for the radio and optical axes of the resolved radio sources(i.e., θ >~ 5") to be correlated or anticorrelated, nor anyevidence for strong clustering around sample radio sources on average.(2) The nearby sample: except for R <~ 15, the sample is dominated byelliptical galaxies with 16 <~ R <~ 18.5 mag and a spectral indexdistribution similar to that of the distant sample. Based on the radialdistribution of optical objects around each radio source, we found thatthe average radio source environment becomes richer from thatcharacteristic of galaxy groups for R < 17 mag (z <~ 0.2) to thatof galaxy groups to clusters at R ~> 18 mag (z ~> 0.3).
| 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.
| The far-infrared properties of the CfA galaxy sample. I - The catalog
IRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths.
| A 1.4 GHz source survey in an area without nearby rich galaxy clusters
The paper reports on 1.4 GHz continuum observations for 56 contiguousVLA fields, using the D configuration, in a region devoid of nearby,rich galaxy clusters (at z less than 0.4). 354 continuum sources aretabulated, with fluxes down to about 1.5 mJy, in an area of about 12 sqdeg. Only about seven of the 354 radio sources are associated with knownrich galaxy clusters at z greater than 0.4 (tabulated by Gunn, Hoessel,and Oke, 1986). Source positions are compared with those from an opticalcatalog and mild correlations on angular scales of order 1 arcmin arefound. This suggests some association of radio sources with galaxygroups (sizes of order 200 kpc) at redshifts of order z = 0.1, eventhough there are no rich galaxy clusters in this redshift range.
| A 21 CM survey of the Pisces-Perseus supercluster. III - The region north of +38 degrees
As part of a comprehensive survey of galaxies in the region of thePisces-Perseus supercluster and its surroundings, 21-cm lineobservations obtained with the NRAO 91-m telescope are presented for 383galaxies in the right ascension range from 22 to 10 hr and north of +38deg declination. Recent improvements to the Green Bank receiver/feedsystem have dramatically raised detection rates at the distance ofPisces-Perseus (cz = +5000 km/s). The present study has contributed todouble the number of known redshifts outside rich clusters in thissection of the sky. The H I content of the current sample, as expressedin terms of the H I mass expected for a galaxy of the same optical sizeand morphology, matches the standard of normalcy established forisolated galaxies.
| A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
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