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A Catalog of H I-Selected Galaxies from the South Celestial Cap Region of Sky
The first deep catalog of the H I Parkes All Sky Survey (HIPASS) ispresented, covering the south celestial cap (SCC) region. The SCC areais ~2400 deg2 and covers δ<-62°. The average rmsnoise for the survey is 13 mJy beam-1. Five hundredthirty-six galaxies have been cataloged according to their neutralhydrogen content, including 114 galaxies that have no previous catalogedoptical counterpart. This is the largest sample of galaxies from a blindH I survey to date. Most galaxies in optically unobscured regions of skyhave a visible optical counterpart; however, there is a small populationof low-velocity H I clouds without visible optical counterparts whoseorigins and significance are unclear. The rms accuracy of the HIPASSpositions is found to be 1.9′. The H I mass range of galaxiesdetected is from ~106 to ~1011 Msolar.There are a large number of late-type spiral galaxies in the SCC sample(66%), compared with 30% for optically selected galaxies from the sameregion in the NASA Extragalactic Database. The average ratio of H I massto B luminosity of the sample increases according to optical type, from1.8 Msolar/Lsolar for early types to 3.2Msolar/Lsolar for late-type galaxies. The HI-detected galaxies tend to follow the large-scale structure traced bygalaxies found in optical surveys. From the number of galaxies detectedin this region of sky, we predict the full HIPASS catalog will contain~5000 galaxies, to a peak flux density limit of ~39 mJy (3 σ),although this may be a conservative estimate as two large voids arepresent in the region. The H I mass function for this catalog ispresented in a subsequent paper.
| Southern Isolated Galaxy Triplets
Seventy-six isolated triple systems of galaxies with declinatiosnδ<-3° were selected using ESO/SERC and POSS-I sky surveydata. The equatorial coordinates, configuration types, angular sizes,component angular separations, component morphological types, totalmagnitudes, and other parameters are reported for each triplet.Radial-velocity estimates are available for all components in 33 of the76 triplets. The median values of the main dynamicalparametersradial-velocity dispersion, mean harmonic radius,absolute magnitudes of member galaxies, and mass-to-luminosityratiosare similar to those obtained earlier for 83 isolatedtriple systems with δ>-3°.
| On the morphology of peculiar ring galaxies
It is proposed that peculiar ring galaxies can be divided into fiveprincipal types according to the morphology of the ring and bulge, basedon the visual inspection of 489 selected objects. Those objects havebeen named ``peculiar'' following the ``Catalogue of Southern PeculiarGalaxies and Associations'' by \cite[Arp & Madore (1986]{am6}) Table2 with its notes is only available electronically via anonymous ftp130.79.128.5 or http://cdsweb.u-strasbg.fr.
| 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.
| A catalogue of spatially resolved kinematics of galaxies: Bibliography
We present a catalogue of galaxies for which spatially resolved data ontheir internal kinematics have been published; there is no a priorirestriction regarding their morphological type. The catalogue lists thereferences to the articles where the data are published, as well as acoded description of these data: observed emission or absorption lines,velocity or velocity dispersion, radial profile or 2D field, positionangle. Tables 1, 2, and 3 are proposed in electronic form only, and areavailable from the CDS, via anonymous ftp to cdsarc.u-strasbg.fr (to130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| NGC 6438: A Triple System?
We provide photographic and photoelectric information as well as CCDimaging and medium resolution spectroscopy on this system located at adistance of ~32 Mpc. The S0 galaxy has twisted isophotes which also showchanges in the ellipticity. Profiles toward the north of this galaxy are0.1 and 0.2 mag brighter in the B and V bands, respectively, than in anyother direction, probably due to the presence of dust in the Irregularsystem. Several blue regions (B-V = 0.26-0.40) are found in theIrregular object indicating ongoing star formation. One of these regionsis located in an extreme of the northern arm, its luminosity beingsimilar to that of the nucleus which is very close to it. Analysis ofthe spectra shows typical absorption lines and a weak [N II] emission inthe S0 galaxy, whereas Hα, [N II], and [S II] emission lines areobserved both in the nucleus and in the blue region mentioned above. Wedetermine a high reddening E(B - V) = 1.4 in the nuclear region of thissystem. Rotation curves show a different behavior for the nucleus andthe blue region, which have V_max_ >= 180 km/s and V_max_ = 80 km/s,respectively. All this evidence could support the idea that NGC 6438 isan interacting triplet, one S0 galaxy and two disk galaxies undergoing amerger.
| Surface photometry of binary galaxies. I. A multicolour study of morphologies due to the interaction.
We present the multicolour (B, V, R) surface photometry of 53 doublegalaxies. All the pairs belong to the catalogue of Reduzzi &Rampazzo (1995) containing objects selected according to theKarachentsev (1972) criteria. We comment on the morphological,structural and photometric characteristics of pairs and their members.Different classes of interaction induced phenomena, both among early andlate-type galaxies, are considered. We found that few early-typegalaxies show fine structures. Grand design structure is more frequentlydetected in binary than in field spirals both for barred and non barred,confirming Elmegreen & Elmegreen's (1982) study. The colour of thetails is consistent with the stripping hypothesis since it is similar tothe progenitor galaxy outskirts. Among our objects we have no evidentsign of induced star formation in tails. Rings appear on average bluerthan the disc as a whole.
| Star formation in early-type galaxies of mixed pairs.
We present optical imaging, spectroscopy and stellar populationsynthesis results for a sample of 4 mixed pairs of galaxies. The dataallow us to estimate the degree of interaction with reasonablecertainty. We conclude that one pair, AM1907-504, is likely to be anoptical alignment. The remaining systems show radial velocitydifferences and morphology consistent with the hypothesis that they arephysical binaries. Surface photometry allowed us to measure tidaldistortions in the spiral components and to identify internal structurein the early-type members. We also made a stellar population synthesisstudy of the early-type components and find evidence for a young stellarpopulation in the central regions of these galaxies. We considerpossible origins for the young component as due either to mass-transferfrom the spiral (cross-fuelling) or accretion events.
| Mixed Pairs of Galaxies
According to many schemes for galaxy formation, galaxy morphology shoulddepend strongly on the environment in which a galaxy resides and,especially, in which it was formed. Therefore, in pairs of galaxies oneexpects to find members of similar morphological type. However,morphological studies of paired galaxies show two different categories:pairs formed by galaxies with similar morphology (EE and SS) and pairsof mixed morphology (ES), where E represents early--type galaxies and Srepresents late--types. Actually a significant percentage of pairs inreasonably complete samples of binary galaxies (e.g. Catalog of IsolatedPairs of Galaxies by Karachentsev) are of mixed type. Moreover, thedistribution of radial velocity differences between components of mixedpairs is similar to that for concordant type (especially SS) pairs. Thisis further support for the contention that most are physical binaries.We used imaging, spectroscopy and stellar population synthesis to studythe interaction effects in 5 mixed pairs of galaxies (AM0327-285,AM1806-852, AM1907-504, AM2016-330, AM2055-492). The present pair sampleoriginated from a sample of 126 candidate mixed pairs that were foundduring a visual search on the ESO sky surveys. An isolation criterionwas employed that required the distance to the nearest neighbor (withmajor axis diameter >= the diameters of the pair components) to be atleast five times the pair component separation. Many of these pairs arealso found in the Catalogue of Southern Peculiar Galaxies andAssociations by Arp & Madore. We find that one of them, AM1907--504,is unlikely to be a physical pair because of the large velocitydifference. The other 4 pairs are most likely physically bound withDelta-V <= 600 km/s. They can also be classified as true ES pairssince the photometric profiles for the early-type components obey anr^1/4 law. We find diverse signs of interaction in our pair sampleranging from direct collisions to small distortions. In principle, thisevidence is less ambiguous in mixed pairs because we are dealing with asingle gas rich component. A strong but indirect form of evidence forinteraction between the galaxies involves the detection of a youngstellar component in the early-type members. We used Bica's stellarsynthesis approach in order to detect the young stellar population inthese pairs. We find that 10% to 37% of their fluxes arises from a youngage population (< 5 x 10^8 years). We suggest that a transfer of gasappears to be the most likely way for the E components to acquire fuelfor star formation activity. The only other alternative would be toinvoke an unusual star formation history in ellipticals that inhabitmixed pairs. (SECTION: Dissertation Summaries)
| Candidates for a southern extension of the Karachentsev catalogue of isolated pairs of galaxies.
Not Available
| Galaxies with f12 > f25
We have compiled a sample of galaxies whose flux density is higher at 12microns (f12) than at 25 microns (f25). It is argued thatf12 >f25effectively selects quiescent galaxies which are less active ininfrared, radio, and optical bands than other types of normal galaxies.Moreover galaxies withf12 >f25 do not exhibit the well-knownrelations that normal galaxies show between far-infrared parameters, forexample, the negative correlation betweenf12/f25 andf60/f100. Thesegalaxies also show different far-infrared and radio properties. In ouropinion this sample of quiescent galaxies is suitable for use as acontrol sample when properties of more active galaxies are discussed. Itmay also be used in modeling galaxies with active star formation or anactive nucleus.
| Compact groups of galaxies in the nearby universe
We have searched for compact groups of galaxies among the largestcatalog of nearby groups (LGG catalog). 21 new compact groups of atleast 3 members were found. Their surface brightnesses are generallylower than those of Hickson compact groups (HCGs), and theircharacteristics are close to those of loose groups. We have alsoretrieved all HCGs of the nearby universe. These are all embedded ingroups, forming the cores or substructures of loose groups. Theseresults suggest that compact groups may form as core or substructureswithin loose groups (like the HCGs), or form from loose groups when theystart collapsing (like those of the LGG).
| Fine structure in the early-type components in mixed pairs of galaxies.
Not Available
| 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.
| Spectroscopic observations of Arp-Madore interacting galaxies. I - Pairs of comparably sized galaxies
Nuclear spectra of 129 galaxies from a sample of 71 pairs of interactingdoubles of comparably sized galaxies have been analyzed on the basis ofIRAS observations. Data obtained include radial velocities, relativeemission-line intensity measurements, and optical classifications. It isconfirmed that a large number of these objects are indeed showing H IIregion type spectra. It is suggested that a low LINER detection ratecould be due to the IR criteria which favor a strong H II region typeactivity and make it difficult to detect low-level LINER activity whichmay be present. The excess of Seyfert-type nuclei was not found, and thereason remains unclear. A high-frequency of one-sided enhancedstar-formation activity, suggested by the far-infrared study of the samesample of galaxies, also was not found. The enhancement of thestar-formation activity more likely to take place in both galaxies, butthe strength and/or time-scale and phase of the activity in each of thetwo galaxies of the pair may differ substantially.
| Galaxies, odd couples.
Not Available
| Quantitative morphology of isolated E/S pairs of galaxies
We present a study of the morphology and geometry for 22 southern E+Spair candidates using high resolution CCD frames obtained at the ESO 2.2m telescope. We find a considerable number of true mixed pairs withabout 13/11 elliptical + spiral pairs in the present sample. Theremaining objects include about 3 'disky' pairs (composed of S0 and Smembers) and 3 'early-type' pairs comprising E and S0 members. Weestimate that between 10 and 25 percent of the pairs in any complete(non-hierarchical) sample will be of the E+S type. This suggests thatmorphological concordance is not the rule among paired galaxies. Wesuggest that interaction phenomena and the alterations they produce ingalaxy forms may explain many of the mixed pairs. Eight early-typecomponents show possible shell structure while 78 percent show anisophotal twisting of greater than 10 deg. Three of these objects andtwo additional pairs may be mergers in progress based upon their chaoticmorphologies. We suggest that the early-type components in many pairscould be merger products. These E+S pairs might then be a transientstage in the coalescence of compact groups.
| A deep redshift survey of IRAS galaxies towards the Bootes void
Redshifts were measured for a complete sample of galaxies detected bythe IRAS within 11.5 deg of the center of the void in Bootes discoveredby Kirshner et al (1981). There are 12 IRAS galaxies within the void asdefined by the above authors, seven of which were discovered in thissurvey. One of these has a companion at the same redshift. The resultingdensity of IRAS galaxies in the void is measured to be between 1/6 and1/3 of the average density; the uncertainty is dominated by Poissonstatistics. Good agreement is found between the selection function andnumber density derived from the present sample and those derived fromthe all-sky sample of Strauss (1989). The optical spectra of the newlyfound galaxies in the void are typical of IRAS galaxies in the field.
| Low-luminosity radio sources in early-type galaxies
A sensitive radio continuum survey of 114 nearby E and S0 galaxies hasbeen made to search for weak sources. The radio detection rate is 42percent, with a flux limit of 0.8 mJy at 5 GHz. By deriving the radioluminosity function for a complete sample, it is shown that most brightearly-type galaxies have low-luminosity nonthermal radio sources.Galaxies of similar optical luminosity vary widely in radio luminosity,but a characteristic radio power rises roughly as the optical luminositysquared. S0 galaxies have weaker radio sources on average thanelliptical galaxies, but this can be explained by the low luminosity ofmost S0 bulges relative to ellipticals. No correlation is found betweenradio power and axial ratio for galaxies with radio luminosities below10 to the 23rd W/Hz.
| On the relationship between radio emission and optical properties in early-type galaxies
To study the origin of radio activity in early-type galaxies, thepossible dependence of their radio emission on basic optical parameters,such as the absolute magnitude, the central velocity dispersion sigma,and the mean surface brightness mu is explored. A sample of 743 E and SOgalaxies is used which is based on three independent radio surveys ofoptically selected galaxies with virtually complete information onmagnitudes, morphological types, redshift distances, diameters, andradio fluxes. For both E and SO galaxies, only the absolute magnitudeappears to be directly related to the radio activity, while sigma and mudo not. Also, a significant dependence of the apparent flattening onradio power is confirmed for E galaxies. Some relevant implications ofthese results are discussed.
| Observations of binary galaxies at a frequency of 102 MHz
A total of 93 double galaxies from the Karachentsev list was observedwith the large phased array at the Lebedev Physical Institute at 102MHz. The interplanetary oscillation method was used. Two of the galaxieswere found to contain scintillating components with angular dimensionsof less than 1 arcsec and flux densities of more than 1 Jy. Theobservations of double galaxies at low radio frequencies indicate thatgalaxies in pairs are more active than single galaxies.
| Magnitude calibration in the Cordoba Atlas
Not Available
| Infrared properties of dusty elliptical galaxies
From published sources including the IRAS survey, a sample of 6 E and S0galaxies with dust lanes and a comparative sample of 32 such galaxieswithout dust lanes were collected. No evidence was found that dustylanes in ellipticals are sites of intensive star formation with strongIR emission. On the IR two-color diagram, ellipticals without dust lanesare located in the same region as normal galaxies, while some of thosewith dust lanes are located far from this region; these are often activegalaxies.
| The local radio luminosity function of galaxies at 843 MHz
Two independent samples of galaxies have been observed with the MolongloObservatory Synthesis Telescope at 843 MHz, and the resulting localradio luminosity function (LRLF) has been extended to radio powers ofabout 10 to the 18th W/Hz per sr. E and S0 galaxies are found to beunimportant to the LRLF at low radio luminosities, but to behave likestandard candles above powers of about 10 exp 22.5 W/Hz per sr. Theobservations suggest that the radio properties of the most massive S0galaxies resemble those of radio ellipticals, while at lowerluminosities the detection rate and radio-optical correlation arecomparable to those of early-type spirals.
| Ionized gas in elliptical and S0 galaxies. I - A survey for H-alpha and forbidden N II emission
A spectroscopic survey of a large sample of southern E and S0 galaxiesin order to detect ionized gas in the nuclei is reported. The strongestline in the 6000-7000 A range was nearly always forbidden N II 6584 A,followed by H-alpha and forbidden S II 6716, 6731 A. Identical detectionrates of about 50 percent were obtained for the forbidden N II line inboth E and S0 galaxies. The mass of ionized gas in early-type galaxieswas very small, with values typically in the range 1000-10,000 solarmasses. The relative emission-line strengths in virtually every casewere indistinguishable from those of LINER nuclei. The observed valuesof the forbidden N II 6584 A/H-alpha ratios fell mostly between one andthree and seem correlated with galaxy absolute magnitude. The existenceof such a correlation may be indicative of metallicity differences.
| Southern Galaxy Catalogue.
Not Available
| Radio and optical observations of a complete sample of E and SO galaxies. III. A radio continuum survey at 2.7 and 5.0 GHz.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...53S&db_key=AST
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