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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
| The IRAS Revised Bright Galaxy Sample
IRAS flux densities, redshifts, and infrared luminosities are reportedfor all sources identified in the IRAS Revised Bright Galaxy Sample(RBGS), a complete flux-limited survey of all extragalactic objects withtotal 60 μm flux density greater than 5.24 Jy, covering the entiresky surveyed by IRAS at Galactic latitudes |b|>5°. The RBGS includes629 objects, with median and mean sample redshifts of 0.0082 and 0.0126,respectively, and a maximum redshift of 0.0876. The RBGS supersedes theprevious two-part IRAS Bright Galaxy Samples(BGS1+BGS2), which were compiled before the final(Pass 3) calibration of the IRAS Level 1 Archive in 1990 May. The RBGSalso makes use of more accurate and consistent automated methods tomeasure the flux of objects with extended emission. The RBGS contains 39objects that were not present in the BGS1+BGS2,and 28 objects from the BGS1+BGS2 have beendropped from RBGS because their revised 60 μm flux densities are notgreater than 5.24 Jy. Comparison of revised flux measurements forsources in both surveys shows that most flux differences are in therange ~5%-25%, although some faint sources at 12 and 25 μm differ byas much as a factor of 2. Basic properties of the RBGS sources aresummarized, including estimated total infrared luminosities, as well asupdates to cross identifications with sources from optical galaxycatalogs established using the NASA/IPAC Extragalactic Database. Inaddition, an atlas of images from the Digitized Sky Survey with overlaysof the IRAS position uncertainty ellipse and annotated scale bars isprovided for ease in visualizing the optical morphology in context withthe angular and metric size of each object. The revised bolometricinfrared luminosity function, φ(Lir), forinfrared-bright galaxies in the local universe remains best fit by adouble power law, φ(L)~Lα, withα=-0.6(+/-0.1) and α=-2.2(+/-0.1) below and above the``characteristic'' infrared luminosityL*ir~1010.5Lsolar,respectively. A companion paper provides IRAS High Resolution (HIRES)processing of over 100 RBGS sources where improved spatial resolutionoften provides better IRAS source positions or allows for deconvolutionof close galaxy pairs.
| An H I/Optical Atlas of Isolated Galaxies
We present an H I and optical survey of 41 extremely isolated galaxiesin an attempt to search for the gaseous remnants of the galaxy formationprocess, predicted to exist by hierarchical models of galaxy formation.By observing extremely isolated, quiescent, nonpeculiar galaxies weminimize the chances that any extragalactic H I found will be anothergalaxy, tidal debris, or ejecta from a galactic fountain or superwind.We have obtained new and archival data from the VLA and ATCA in a searchfor H I clouds down to MHI~107 Msolararound these galaxies. We found 13 H I-rich companions around 10 of the41 galaxies surveyed. Optical imaging finds spatially coincident starsassociated with all 13 companions. We find that the isolated galaxieshave properties fairly similar to those of field galaxies, while thecompanions are similar to dwarf irregular galaxies. The presence ofstars in all 13 companions suggests that H I clouds without starsdiscovered by other authors around field galaxies are not primordial andmost likely have either a tidal or ejecta origin.
| A catalog of galaxies behind the Southern Milky Way . I. The Hydra/Antlia extension (l~ 266or - 296or)
A deep optical galaxy search in the southern Milky Way - aimed atreducing the width of the Zone of Avoidance - revealed 3279 galaxycandidates above the diameter limit of D >~ 0.2', of which only 112(3.4%) were previously catalogued. The surveyed region (266o<~ \ell <~ 296o and -10o <~ b <~+8o) lies in the extension of the Hydra and Antlia clusters -where a supercluster is suspected - and in the approximate direction ofthe dipole anisotropy in the Cosmic Microwave Background radiation. Herewe present the optical properties of the unveiled galaxies such aspositions, diameters, magnitudes, morphological types, including adetailed discussion on the quality of these data and the completenesslimits as a function of the foreground dust extinction. For 127 of the227 positional matches in the IRAS PSC, a reliable cross-identificationcould be found. Several distinct overdensities and filaments of galaxiescan be identified that are apparently uncorrelated with the Galacticforeground extinction hence the probable signature of extragalacticlarge-scale structures. This catalog constitutes the first part in aseries of five equally conducted optical searches for galaxies in thesouthern Milky Way (245o <~ \ell <~ 350o).With these surveys, the entire Zone of Avoidance will have been coveredby means of visual inspection. The catalogs build the basis for variousspectroscopic and photometric follow-up programs which eventually willallow a thorough analyse of the galaxy distribution in redshift spaceand the peculiar velocity fields within the Zone of Avoidance, as wellan an improved understanding of the Galactic foreground extinction.Tables 1 and 2 are available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Redshift Distribution of Galaxies in the Southern Milky Way Region 210 degrees < L < 360 degrees and B < 15 degrees
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..107..521V&db_key=AST
| Dust and CO emission in normal spirals. I. The data.
We present 1300μm continuum observations and measurements of the CO(1-0) and (2-1) emission from the inner regions of 98 normal galaxies.The spatial resolution ranges from 11" to 45". The sources come from acomplete FIR selected sample of 138 inactive spirals with an opticaldiameter D_25_<=180".
| The IRAS Bright Galaxy Survey - Part II: Extension to Southern Declinations (delta ~< -30), and Low Galactic Latitudes (f<|b|
Complete IRAS Observations and redshifts are reported for all sourcesidentified in the IRAS Bright Galaxy Survey-Part II (hereafter referredto as BGS_2_). Source positions, radial velocities, optical magnitudes,and total flux densities, peak flux densities, and spatial extents at12, 25, and 100 ,microns are reported for 288 sources having 60 micronflux densities > 5.24 Jy, the completeness limit of the originalBright Galaxy Survey [Soifer et al., AJ, 98,766(1989)], hereafterreferred to as BGS_1_. These new data represent the extension of theIRAS Bright Galaxy Survey to southern declinations,δ<~-30^deg^, and low Galactic latitudes,5^deg^<|b|<30^deg^. Although the sky coverage of the BGS_2_ (~19935 deg^2^) is 37% larger than the sky coverage of the BGS_1_, thenumber of sources is 8% smaller due primarily to large scale structurein the local distribution of galaxies. Otherwise, the sources in theBGS_2_ show similar relationships between number counts and flux densityas observed for the 313 sources in the BGS_1_. The BGS_2_ along with theearlier BGS, represents the best sample currently available for definingthe infrared properties of galaxies in the local (z <~ 0.1) Universe.
| Dust in spiral galaxies, 2
We have mapped 32 non-active spirals at 1300 micrometers and measured 7of them at 450 and 800 micrometers. We determine gas masses, dusttemperatures and IR luminosities. From a detailed analysis we find: (1)The spatial extent of the cold dust is comparable to the optical size ofthe galaxies. About 70% of the mass is contained within half the opticalradius; there the gas surface density decreases inversely proportionalto the galactocentric radius. (2) The new submm data set limits on thedecomposition of the FIR spectra into dust components of differenttemperatures. The flux ratios of 450 to 1300 micrometers suggest twokinds of nonactive spirals: those with S450micrometers/S1300 micrometers approximately equal to40, like the Milky Way, where the coldest dust is approximately 20K andaccounts for most of the emission between 100 and 1300 micrometers; onthe other hand, there are galaxies with S450micrometers/S1300 micrometers approximately 20 whichimplies that most of the interstellar dust is extremely cold(approximately 10 K). (3) The ratio of infrared luminosity to gas mass,LIR/Mgas, equals 5 +/- 2 in solar units. Foractive galaxies from the Markarian catalog this ratio is 20 timeslarger. Therefore LIR/Mgas gives a clear signaturefor the activity stage.
| A search for IRAS galaxies behind the southern Milky Way
We systematically searched for IRAS galaxies with 60 micrometer fluxdensity larger than 0.6 Jy by using the UK Schmidt Infrared and IIIa-JAtlases in the Milky Way region (absolute value of b less than 15 deg)between l = 210 deg and 360 deg. We first selected about 4000 IRAS pointsources by using our far-infrared criteria, which are optimized for thesearch of IRAS galaxies behind the Milky Way region, and then inspectedvisually the optical counterparts of them on the Schmidt Atlas filmcopies. We found 966 IRAS sources associated with galaxy-like objects.The list of the objects is presented here with the IRAS source name,Galactic coordinates, IRAS flux densities, field number and emulsion ofthe Atlas, type and size of galaxy (-like) image, redshift,multiplicity, and cross-identification. Of these, 423 galaxies arealready cataloged in the Catalog of Galaxies and Quasars Observed in theIRAS Survey, and most of the remaining 543 galaxy candidates are newlyidentified in this search. Although the radial velocities are known foronly 387 galaxies, of which 60 were newly measured by us so far, weinferred the contamination by Galactic objects to be small from the goodcorrelation between the sky distributions of the newly identified galaxycandidates and the previously cataloged galaxies. In the regions wherethe Galactic molecular clouds dominate, almost all the sources were notidentified as galaxies. The detected galaxies are clustered in the threeregions around l = 240 deg, 280 deg, and 315 deg, where the projectednumber densities are higher than the whole-sky average of IRAS galaxiesof the same flux limit.
| IRAS LRS spectroscopy of galaxies
The study presents IRAS LRS data for 350 galaxies with pointlike IRASsources having either S(12) or S(25) not less than 1.5 Jy. Techniquesare presented which form the mean of an ensemble of LRS spectra, ll ofwhich are only of low signal-to-noise ratio, by quantitative evaluationof the significance of the individual spectra for each object ratherthan mere acceptance of the 'average spectrum' present in the completeLRS data base. Average LRS spectra for groups of galaxies with distinctoptical nuclear properties are formed. Average LRS spectra for severalcategories of objects are presented and interpreted. H II regiongalaxies show the polycyclic aromatic hydrocarbon spectrum of bands inemissions; type 2 Seyferts present a broad emission feature parking near16 microns; LINERs and galaxies without optical emission lines have LRSspectra that decline with wavelength, whereas type 1 Seyferts and WRgalaxies have red spectra suggestive of nonthermal emission processes.
| The supergalactic plane redshift survey
Redshift measurements, about 1000 of which are new, are presented for1314 galaxies in a survey toward the apex of the large-scale streamingflow for ellipticals. The velocity histogram shows that the excess ingalaxy number counts in this area is due to a substantial concentrationof galaxies with discrete peaks at V about 3000 km/s and V about 4500km/s. After correction for the sampling function, the centroid of thedensity distribution is found to be near V about 4500 km/s.Normalization to the more extensive SSRS survey, which was selected bythe same criteria, shows that the region studied contains a considerableoverdensity of galaxies from 2000 to 6000 km/s. This result is in goodagreement with the 'great attractor' model suggested by Lynden-Bell etal. (1988) which attributes the peculiar motions of elliptical galaxiesover a large region of space to an extensive mass overdensity whichincludes the Hydra-Centaurus and Pavo-Indus superclusters. The centroidof the density enhancement is also consistent with new data by Dresslerand Faber (1990) of peculiar motions of elliptical and spiral galaxies,both of which show a zero crossing of the Hubble line at approximately4500-5000 km/s.
| Southern Galaxy Catalogue.
Not Available
| An optical and H I study of late-type low surface brightness galaxies
Neutral hydrogen and optical parameters are presented for 151 galaxiesof low surface brightness selected from UK Schmidt plates. The 21-cm H Iline was detected in 100 of these systems. It is found that the galaxiesshow the same trends of global properties with type as samples of brightgalaxies, while the data are consistent with the low surface brightness(LSB) galaxies being of systematically lower mass than bright galaxiesof the same type and linear dimensions. A constant value of hydrogenmass/(linear dimension)/squared is strongly suggested for LSB and brightgalaxies.
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