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HI content in galaxies in loose groups
Gas deficiency in cluster spirals is well known and ram-pressurestripping is considered the main gas removal mechanism. In some compactgroups too gas deficiency is reported. However, gas deficiency in loosegroups is not yet well established. Lower dispersion of the membervelocities and the lower density of the intragroup medium in small loosegroups favour tidal stripping as the main gas removal process in them.Recent releases of data from the HI Parkes All-Sky Survey (HIPASS) andcatalogues of nearby loose groups with associated diffuse X-ray emissionhave allowed us to test this notion. In this paper, we address thefollowing questions: (i) do galaxies in groups with diffuse X-rayemission statistically have lower gas content compared to the ones ingroups without diffuse X-ray emission? (ii) does HI deficiency vary withthe X-ray luminosity, LX, of the loose group in a systematicway? We find that (i) galaxies in groups with diffuse X-ray emission, onaverage, are HI deficient, and have lost more gas compared to those ingroups without X-ray emission; the latter are found not to havesignificant HI deficiency; (ii) no systematic dependence of the HIdeficiency with LX is found. Ram-pressure-assisted tidalstripping and evaporation by thermal conduction are the two possiblemechanisms to account for this excess gas loss.
| Ultraluminous X-Ray Sources in Nearby Galaxies from ROSAT High Resolution Imager Observations I. Data Analysis
X-ray observations have revealed in other galaxies a class ofextranuclear X-ray point sources with X-ray luminosities of1039-1041 ergs s-1, exceeding theEddington luminosity for stellar mass X-ray binaries. Theseultraluminous X-ray sources (ULXs) may be powered by intermediate-massblack holes of a few thousand Msolar or stellar mass blackholes with special radiation processes. In this paper, we present asurvey of ULXs in 313 nearby galaxies withD25>1' within 40 Mpc with 467 ROSAT HighResolution Imager (HRI) archival observations. The HRI observations arereduced with uniform procedures, refined by simulations that help definethe point source detection algorithm employed in this survey. A sampleof 562 extragalactic X-ray point sources withLX=1038-1043 ergs s-1 isextracted from 173 survey galaxies, including 106 ULX candidates withinthe D25 isophotes of 63 galaxies and 110 ULX candidatesbetween 1D25 and 2D25 of 64 galaxies, from which aclean sample of 109 ULXs is constructed to minimize the contaminationfrom foreground or background objects. The strong connection betweenULXs and star formation is confirmed based on the striking preference ofULXs to occur in late-type galaxies, especially in star-forming regionssuch as spiral arms. ULXs are variable on timescales over days to yearsand exhibit a variety of long term variability patterns. Theidentifications of ULXs in the clean sample show some ULXs identified assupernovae (remnants), H II regions/nebulae, or young massive stars instar-forming regions, and a few other ULXs identified as old globularclusters. In a subsequent paper, the statistic properties of the surveywill be studied to calculate the occurrence frequencies and luminosityfunctions for ULXs in different types of galaxies to shed light on thenature of these enigmatic sources.
| A new catalogue of ISM content of normal galaxies
We have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of ``normality''. Thedefinition of a ``normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for ``normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5
| A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere
A catalog of optical warps of galaxies is presented. This can beconsidered complementary to that reported by Sánchez-Saavedra etal. (\cite{sanchez-saavedra}), with 42 galaxies in the northernhemisphere, and to that by Reshetnikov & Combes(\cite{reshetnikov99}), with 60 optical warps. The limits of the presentcatalog are: logr 25 > 0.60, B_t< 14.5, delta (2000) <0deg, -2.5 < t < 7. Therefore, lenticular galaxies havealso been considered. This catalog lists 150 warped galaxies out of asample of 276 edge-on galaxies and covers the whole southern hemisphere,except the Avoidance Zone. It is therefore very suitable for statisticalstudies of warps. It also provides a source guide for detailedparticular observations. We confirm the large frequency of warpedspirals: nearly all galaxies are warped. The frequency and warp angle donot present important differences for the different types of spirals.However, no lenticular warped galaxy has been found within the specifiedlimits. This finding constitutes an important restriction fortheoretical models.
| Warps and correlations with intrinsic parameters of galaxies in the visible and radio
From a comparison of the different parameters of warped galaxies in theradio, and especially in the visible, we find that: a) No large galaxy(large mass or radius) has been found to have high amplitude in thewarp, and there is no correlation of size/mass with the degree ofasymmetry of the warp. b) The disc density and the ratio of dark toluminous mass show an opposing trend: smaller values give moreasymmetric warps in the inner radii (optical warps) but show nocorrelation with the amplitude of the warp; however, in the externalradii is there no correlation with asymmetry. c) A third anticorrelationappears in a comparison of the amplitude and degree of asymmetry in thewarped galaxies. Hence, it seems that very massive dark matter haloeshave nothing to do with the formation of warps but only with the degreeof symmetry in the inner radii, and are unrelated to the warp shape forthe outermost radii. Denser discs show the same dependence.
| Nearby Optical Galaxies: Selection of the Sample and Identification of Groups
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
| Box- and peanut-shaped bulges. I. Statistics
We present a classification for bulges of a complete sample of ~ 1350edge-on disk galaxies derived from the RC3 (Third Reference Catalogue ofBright Galaxies, de Vaucouleurs et al. \cite{rc3}). A visualclassification of the bulges using the Digitized Sky Survey (DSS) inthree types of b/p bulges or as an elliptical type is presented andsupported by CCD images. NIR observations reveal that dust extinctiondoes almost not influence the shape of bulges. There is no substantialdifference between the shape of bulges in the optical and in the NIR.Our analysis reveals that 45% of all bulges are box- and peanut-shaped(b/p). The frequency of b/p bulges for all morphological types from S0to Sd is > 40%. In particular, this is for the first time that such alarge frequency of b/p bulges is reported for galaxies as late as Sd.The fraction of the observed b/p bulges is large enough to explain theb/p bulges by bars. Partly based on observations collected at ESO/LaSilla (Chile), DSAZ/Calar Alto (Spain), and Lowell Observatory/Flagstaff(AZ/U.S.A.). Tables 6 and 7 are only available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Very Wide Galaxy Pairs of the Northern and Southern Sky
We present highly accurate observations of the 21 cm line of hydrogen ingalaxies made at the Arecibo and Parkes Observatories. The galaxiesobserved have been identified, through rigorous selection criteriaapplied to the CfA and SSRS catalogs, as being members of pairs withprojected separations of up to 1.5 Mpc (H0 = 75 km s-1 Mpc-1). Theseobservations form the completion of the Chengalur-Nordgren galaxy pairsample with data previously published by Chengalur, Nordgren andcolleagues. The new selection criteria used in this paper are anextension to larger projected separations of the criteria usedpreviously. Forty-nine new galaxies are observed, while H I is detectedin 41 of them. With the addition of these galaxies, the completed samplehas highly accurate H I velocities for a total of 219 galaxies.
| The Southern Sky Redshift Survey
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
| Catalogue of HI maps of galaxies. I.
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| An Einstein X-Ray Survey of Optically Selected Galaxies. I. Data
We present the results of a complete Einstein imaging proportionalcounter X-ray survey of optically selected galaxies from theShapley-Ames Catalog, the Uppsala General Catalogue, and the EuropeanSouthern Observatory Catalog. Well-defined optical criteria are used toselect the galaxies, and X-ray fluxes are measured at the opticallydefined positions. The result is a comprehensive list of X-ray detectionand upper limit measurements for 1018 galaxies. Of these, 827 haveeither independent distance estimates or radial velocities. Associatedoptical, redshift, and distance data have been assembled for thesegalaxies, and their distances come from a combination of directlypredicted distances and those predicted from the Faber-Burstein GreatAttractor/Virgocentric infall model. The accuracy of the X-ray fluxeshas been checked in three different ways; all are consistent with thederived X-ray fluxes being of <=0.1 dex accuracy. In particular,there is agreement with previously published X-ray fluxes for galaxiesin common with a 1991 study by Roberts et al. and a 1992 study byFabbiano et al. The data presented here will be used in further studiesto characterize the X-ray output of galaxies of various morphologicaltypes and thus to enable the determination of the major sourcescontributing to the X-ray emission from galaxies.
| The I band Tully-Fisher relation for cluster galaxies: data presentation.
Observational parameters which can be used for redshift-independentdistance determination using the Tully-Fisher (TF) technique are givenfor \ntot spiral galaxies in the fields of 24 clusters or groups. I bandphotometry for the full sample was either obtained by us or compiledfrom published literature. Rotational velocities are derived either from21 cm spectra or optical emission line long-slit spectra, and convertedto a homogeneous scale. In addition to presenting the data, a discussionof the various sources of error on TF parameters is introduced, and thecriteria for the assignment of membership to each cluster are given.
| Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
| Shell colors in the peculiar elliptical galaxy IC 1459
The giant elliptical galaxy IC 1459 shows a variety of features normallyascribed to a previous encounter with another galaxy, such as acounter-rotating core, nuclear dust lane and an arm-like feature in theemission-line gas. One notable omission from this list was the presenceof stellar shells. Here we present deep CCD imaging of IC 1459 taken B,V, and R filters covering 13.5 min X 13.5 min. After careful modelsubtraction, we have identified several shells and other fine structurearound the galaxy. Shell colors have been measured and are found to besimilar to the underlying galaxy. We briefly discuss the origin of theshells and other peculiarities of IC 1459.
| Galaxy properties in different environments. 1: The sample
This paper presents two galaxy samples, respectively in a high and in alow local density environments, that were generated from the SouthernSky Redshift Survey (SSRS) catalog using objective criteria. Apreliminary comparison of physical properties in these two samplesreveals that galaxies in high-density environments tend to be under ahigher starbursting activity, have a deficiency of the neutral hydrogencontent, present a higher fractional Seyfert population and a higherfraction of barred spirals as well. The present samples are intended tobe used in future spectroscopic observations for more detailedinvestigation.
| Dynamics of the Pavo-Indus and Grus clouds of galaxies
A study of groups of galaxies in the above regions was carried out byselecting a sample extending one magnitude deeper than previous work inthe area, complete down to 15 mag. We report new redshift determinationsfor 58 galaxies in the region and 13 other miscellaneous galaxies, basedon La Silla observations. Using a total of 266 galaxies with measuredredshifts in the Pavo-Indus and Grus clouds, we perform a new analysisof groupings following a well-tested algorithm. A total of 18 groups issingled out, most of them known from previous work, even though a fewadditional members are added. For all the groups, we have calculateddynamical parameters and M/L ratios. All groups are found to be boundaggregates, but only one group can be virialized. For the six mostpopulated examples, having at least five members, we also calculateseveral mass estimators and discuss the wide range of observed M/Lratios, which extends from nine to nearly 500 M(solar)/L(solar). Weintroduce two parameters to measure the presence of either a dominantgalaxy or internal subcondensations, respectively, and test whether anycorrelation with the M/L ratios can be detected. No clear correlationsare found.
| 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.
| A southern sky survey of the peculiar velocities of 1355 spiral galaxies
The paper presents data from photometric and spectroscopic observationsof 1355 southern spiral galaxies and uses them to determine theirdistances and peculiar velocities via the Tully-Fisher (TF) relation.I-band CCD surface photometry was carried out using the 1-m and 3.9-mtelescopes at Siding Spring Observatory. H-alpha rotation curves for 965galaxies and 551 H I profiles are presented. The physical parameters,photometric and velocity data, distances, and peculiar velocities of thegalaxies are presented in tabular form. The mean distance, systemicvelocity, and average peculiar velocity of 24 clusters in the sample aregiven. TF diagrams are presented for each cluster.
| Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.
| Southern Sky Redshift Survey - The catalog
The catalog of radial velocities for galaxies which comprise thediameter-limited sample of the Southern Sky Redshift Survey ispresented. It consolidates the data of observations carried out at theLas Campanas Observatory, Observatorio Nacional, and South AfricanAstronomical Observatory. The criteria used for the sample selection aredescribed, as well as the observational procedures and the techniqueutilized to obtain the final radial velocities. The intercomparisonbetween radial velocity measurements from different telescopes indicatesthat the final data base is fairly homogeneous with a typical error ofabout 40 km/s. The sample is at present 90 percent complete, and themissing galaxies are predominantly objects with very low surfacebrightness for which it is very difficult to obtain optical redshifts.
| A catalog of southern groups of galaxies
A catalog of groups of galaxies identified in the southern Galactic capis presented. This catalog was constructed utilizing the group-findingalgorithm developed by Huchra and Geller (1982) to analyze galaxysamples with well-defined selection criteria and complete velocityinformation.
| The group environment of Seyfert galaxies. II - Spectrophotometry of galaxies in groups
Medium-resolution spectrophotometric data of 104 galaxies have beenobtained. These galaxies are members of 22 loose groups of less thanabout 1 Mpc size. Thirteen of these groups contain Seyfert galaxies.This paper presents calibrated emission-line data and absolute opticalspectra of the individual galaxies as well as plates of each group.
| The group environment of Seyfert galaxies.
On Palomar and ESO Schmidt plates loose groups of 1 Mpc size areidentified. Spectroscopy of 15 such groups containing a Seyfert galaxyand 9 loose groups without a Seyfert galaxy comprising a total number of113 galaxies is presented. Using qualitative and absolute opticalspectroscopic criteria, the activity pattern in groups is described.Galaxies with strong emission-line activity are found in Seyfert groupsout to distances 300 kpc away from the Seyfert galaxy while innon-Seyfert groups such galaxies are virtually absent. The theoreticalimplications of these results with regard to the structural anddynamical conditions for tidally induced starburst and Seyfert activityare discussed.
| Southern Galaxy Catalogue.
Not Available
| H I line studies of galaxies. III - Distance moduli of 822 disk galaxies
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
| 21-cm line profiles of 392 spiral galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982A&AS...50..101B&db_key=AST
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