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# NGC 4799

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 H I observations of galaxies. II. The Coma SuperclusterHigh sensitivity 21-cm H i line observations with an rms noise level of~0.5 mJy were made of 35 spiral galaxies in the Coma Supercluster, usingthe refurbished Arecibo telescope, leading to detection of 25 objects.These data, combined with the measurements available in the literature,provide the set of H i data for 94% of all late-type galaxies in theComa Supercluster with an apparent photographic magnitude mp≤ 15.7 mag. We confirm that the typical scale of H i deficiencyaround the Coma cluster is 2 Mpc, i.e. one virial radius. Comparing theH i mass function (HIMF) of cluster with non-cluster members of the ComaSupercluster we detected a shortage of high H i mass galaxies amongcluster members that can be attributed to the pattern of H i deficiencyfound in rich clusters. The ISOPHOT 170 μm Serendipity Survey II. The catalog of optically identified galaxies%The ISOPHOT Serendipity Sky Survey strip-scanning measurements covering≈15% of the far-infrared (FIR) sky at 170 μm were searched forcompact sources associated with optically identified galaxies. CompactSerendipity Survey sources with a high signal-to-noise ratio in at leasttwo ISOPHOT C200 detector pixels were selected that have a positionalassociation with a galaxy identification in the NED and/or Simbaddatabases and a galaxy counterpart visible on the Digitized Sky Surveyplates. A catalog with 170 μm fluxes for more than 1900 galaxies hasbeen established, 200 of which were measured several times. The faintest170 μm fluxes reach values just below 0.5 Jy, while the brightest,already somewhat extended galaxies have fluxes up to ≈600 Jy. For thevast majority of listed galaxies, the 170 μm fluxes were measured forthe first time. While most of the galaxies are spirals, about 70 of thesources are classified as ellipticals or lenticulars. This is the onlycurrently available large-scale galaxy catalog containing a sufficientnumber of sources with 170 μm fluxes to allow further statisticalstudies of various FIR properties.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) areMPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena,Imperial College London.Full Table 4 and Table 6 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39 HYPERLEDA. II. The homogenized HI dataAfter a compilation of HI data from 611 references and new observationsmade in Nançay, we produce a catalog of homogenized HI data for16781 galaxies. The homogenization is made using the EPIDEMIC methodfrom which all data are progressively converted into the adoptedstandard. The result is a catalog giving: 1) the logarithm of twice themaximum rotation velocity, log 2V_Msin i, converted to thesystem of Mathewson et al. (\cite{Mathewson1996}). This quantity isgiven without correction for inclination; 2) the HI magnitude,m21, (area of the 21-cm line width expressed in magnitude)converted to the flux system of Theureau et al. (\cite{Theureau1998});3) the HI velocity, V_HI, expressed with the optical definition (i.e.,using wavelengths instead frequencies). The typical uncertainties are:0.04 for log 2V_Msin i, 0.25 mag for m21 and 9 kms-1 for V_HI.Full Tables \ref{epidemicw}, \ref{epidemicw2}, \ref{epidemicf},\ref{epidemicf2} and Fig. \ref{profiles} are available in electronicform at http://www.edpsciences.org. Full Tables \ref{references},\ref{cataf}, \ref{newdata} and \ref{notes} are available in electronicform 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/A+A/412/57 A CCD Study of the Environment of Seyfert Galaxies. III. Host Galaxies and the Nearby EnvironmentsA technique is described that permits the robust decomposition of thebulge and disk components of a sample of Seyfert galaxies, as well as a(control) sample of nonactive galaxies matched to the Seyferts in thedistributions of redshift, luminosity, and morphological classification.The structural parameters of the host galaxies in both samples aremeasured. No statistically significant differences at greater than the95% level are found in these parameters according to aKolmogorov-Smirnov test. Companion galaxies''-defined as any galaxywithin a projected separation of 200 h-1 kpc from the centerof the host-are identified and their basic properties measured. Acomparison between the active and control samples in the distributionsof apparent R magnitude, absolute R magnitude (assuming the companionsare at the distance of the host), projected separation from the host,position angle relative to the host, magnitude difference between thecompanion and host, and strength of the tidal parameter shows nostatistically significant differences. Similarly, no statisticallysignificant differences are found between the control and active samplehost galaxies in terms of light asymmetries-bars, rings, isophotaltwisting, etc. The implications for a model in which interactions andmergers are responsible for inciting activity in galactic nuclei arediscussed briefly. The QDOT all-sky IRAS galaxy redshift surveyWe 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 GalaxiesWe 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. A Complete Redshift Survey to the Zwicky Catalog Limit in a 2^h X 15 deg Region around 3C 273We compile 1113 redshifts (648 new measurements, 465 from theliterature) for Zwicky catalog galaxies in the region (-3.5d <= delta<= 8.5d, 11h5 <= alpha <= 13h5). We include redshifts for 114component objects in 78 Zwicky catalog multiplets. The redshift surveyin this region is 99.5% complete to the Zwicky catalog limit, m_Zw =15.7. It is 99.9% complete to m_Zw = 15.5, the CfA Redshift Survey(CfA2) magnitude limit. The survey region is adjacent to the northernportion of CfA2, overlaps the northernmost slice of the Las CampanasRedshift Survey, includes the southern extent of the Virgo Cluster, andis roughly centered on the QSO 3C 273. As in other portions of theZwicky catalog, bright and faint galaxies trace the same large-scalestructure. A CCD Study of the Environment of Seyfert Galaxies. I. The SurveyLarge-format, R-band CCD data are presented for a spectroscopicallycomplete sample of 34 Seyfert galaxies and a control sample of 45nonactive galaxies that are well matched to the Seyfert sample inredshift, luminosity, and morphological type. Gray-scale images of thelocal environment are included for all of the host galaxies, as well asfigures showing the surface brightness, ellipticity, and position angleof the major axis as a function of radius. These data will be used tostudy the environments of these galaxies and hence to test the"interaction hypothesis" that, over the past two decades, has beenimplicated as the triggering mechanism for nuclear activity. While thereare no dramatic differences in most parameters between the active andnonactive samples, the distributions of ellipticities and major-axisposition-angle excursions of the Seyfert host galaxies and the controlgalaxies are marginally different. A higher proportion of Seyfertgalaxies appear to be involved in late-stage mergers. A similar fractionof the control sample, however, displays significant light asymmetriesthat could be evidence for recent interactions. Moreover, a small butsubstantial number of the Seyfert galaxies show no evidence for recentinteractions as judged by the absence of light asymmetries. The far-infrared properties of the CfA galaxy sample. I - The catalogIRAS 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 survey of galaxy redshifts. IV - The dataThe 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. A radio continuum survey at 1.4 GHz of the galaxies in the Virgo regionRadio continuum observations made with the Westerbork Synthesis RadioTelescope at 1.4 GHz are presented for 274 galaxies in the Virgo Clusterregion. The observations are partly full syntheses and partly east-weststrip distributions. For the 55 detected galaxies the emission isseparated into central and extended components. A brief summary of theanalysis is also given.
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