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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
| Properties of isolated disk galaxies
We present a new sample of northern isolated galaxies, which are definedby the physical criterion that they were not affected by other galaxiesin their evolution during the last few Gyr. To find them we used thelogarithmic ratio, f, between inner and tidal forces acting upon thecandidate galaxy by a possible perturber. The analysis of thedistribution of the f-values for the galaxies in the Coma cluster leadus to adopt the criterion f ≤ -4.5 for isolated galaxies. Thecandidates were chosen from the CfA catalog of galaxies within thevolume defined by cz ≤5000 km s-1, galactic latitudehigher than 40o and declination ≥-2.5o. Theselection of the sample, based on redshift values (when available),magnitudes and sizes of the candidate galaxies and possible perturberspresent in the same field is discussed. The final list of selectedisolated galaxies includes 203 objects from the initial 1706. The listcontains only truly isolated galaxies in the sense defined, but it is byno means complete, since all the galaxies with possible companions underthe f-criterion but with unknown redshift were discarded. We alsoselected a sample of perturbed galaxies comprised of all the diskgalaxies from the initial list with companions (with known redshift)satisfying f ≥ -2 and \Delta(cz) ≤500 km s-1; a totalof 130 objects. The statistical comparison of both samples showssignificant differences in morphology, sizes, masses, luminosities andcolor indices. Confirming previous results, we found that late spiral,Sc-type galaxies are, in particular, more frequent among isolatedgalaxies, whereas Lenticular galaxies are more abundant among perturbedgalaxies. Isolated systems appear to be smaller, less luminous and bluerthan interacting objects. We also found that bars are twice as frequentamong perturbed galaxies compared to isolated galaxies, in particularfor early Spirals and Lenticulars. The perturbed galaxies have higherLFIR/LB and Mmol/LB ratios,but the atomic gas content is similar for the two samples. The analysisof the luminosity-size and mass-luminosity relations shows similartrends for both families, the main difference being the almost totalabsence of big, bright and massive galaxies among the family of isolatedsystems, together with the almost total absence of small, faint and lowmass galaxies among the perturbed systems. All these aspects indicatethat the evolution induced by interactions with neighbors would proceedfrom late, small, faint and low mass Spirals to earlier, bigger, moreluminous and more massive spiral and lenticular galaxies, producing atthe same time a larger fraction of barred galaxies but preserving thesame relations between global parameters. The properties we found forour sample of isolated galaxies appear similar to those of high redshiftgalaxies, suggesting that the present-day isolated galaxies could bequietly evolved, unused building blocks surviving in low densityenvironments.Tables \ref{t1} and \ref{t2} are only available in electronic form athttp://www.edpsciences.org
| Physical Coupling of Kazarian Galaxies with Surrounding Galaxies
Results from a statistical study of Kazarian galaxies and the objectssurrounding them are presented. It is shown that: (1) the sample ofKazarian galaxies up to 16m.0 is complete. (2) Roughly 35.7% of theKazarian galaxies are members of clusters, 14.0% of groups, and 13.6% ofbinary systems, while 36.7% are single galaxies. (3) Of the 580 Kazariangalaxies, roughly 61.2% are infrared, 8.8% radio, and 2.8% x-raysources. (4) The relative numbers of Kazarian galaxies for completesamples of I, R, and X in the different groups are systematically higherthan the corresponding numbers for samples of all Kazarian galaxies.
| A CCD Study of the Environment of Seyfert Galaxies. III. Host Galaxies and the Nearby Environments
A 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.
| 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.
| A CCD Study of the Environment of Seyfert Galaxies. I. The Survey
Large-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.
| Bright galaxies from WENSS. I. The minisurvey
A search for bright galaxies associated with radio sources from theWENSS minisurvey has been carried out. A galaxy counterpart was foundfor 402 of almost 10,000 radio sources. Of these a radio and opticallycomplete sample, with a flux density limit at 325 MHz of 30 mJy and alimiting red magnitude of 16, can be constructed, which contains 119galaxies. This paper is the first step of a more general study, in whichwe aim to derive a bright galaxy sample from the entire WENSS survey(which is now available in the public domain) and thus to constructpractically definitive local radio luminosity functions of ellipticaland spiral galaxies. We briefly describe the WENSS minisurvey, and thesteps that are needed for the optical identification of its radiosources. Due to the large numbers of sources involved (over 200,000)completely automated procedures are obviously needed and we discussthese in some detail. It is shown that with modern utilities projects asdescribed here have become quite feasible. Some results (e.g. apreliminary determination of the local radio luminosity function) arepresented. Table 1 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Morphological classification of new galaxies with a UV excess
The results of a morphological classification of 580 galaxies with a UVexcess, included in the lists in [M. A. Kazarian, Astrofizika,15, 5(1979); ibid.,15, 193 (1979); M. A. Kazarian and É. S. Kazarian,ibid.,16, 17 (1980); ibid.,18, 512 (1982); ibid.,19, 213 (1983)], arepresented. For this we have developed a set of symbols, using the typesE, S, and Ir introduced by Hubble, as well as symbols introduced byother authors and us. This set enabled us to make the morphologicalclassification. Direct photographs obtained on the 2.6-m and 6-mtelescopes were used to classify 141 of the galaxies (over 24%), whilePalomar Atlas charts were used for the remaining 439 galaxies. Thesegalaxies were divided into two groups based on classificationconditions, and data on each group are given in Tables 1 and 2,respectively. The results for each group, given in Table 3, show thatwith the transition from early types, such as C and E, to later types,such as S and Ir, the relative number of galaxies going into one group(Table 1), in which the classification was based on direct photographs,increases in comparison with the number going into the other group(Table 2).
| 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.
| 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.
| HI observations of galaxies in nearby Zwicky clusters
The results of a long term project of H I observations of galaxieswithin the boundaries of nearby Zwicky clusters are presented. Thedetection rate is rather low (233 out of 618, i.e., 38 percent) ascompared to other surveys carried out recently. Most of the radialvelocities of the detected galaxies are new determinations. The largespread in radial velocities for many of these clusters is a strongindication for the presence of several foreground and/or backgroundgalaxies.
| 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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