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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
| The UZC-SSRS2 Group Catalog
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
| 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
| 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.
| Nançay ``blind'' 21 CM line survey of the Canes Venatici group region
A radio spectroscopic driftscan survey in the 21 cm line with theNançay decimetric radio telescope of 0.08 steradians of sky inthe direction of the constellation Canes Venatici covering aheliocentric velocity range of -350 < V_hel < 2350 km s(-1)produced 53 spectral features, which was further reduced to a sample of33 reliably detected galaxies by extensive follow-up observations. Witha typical noise level of rms = 10 mJy after Hanning smoothing, thesurvey is - depending on where the detections are located with regard tothe centre of the beam - sensitive to M_HI = 1-2x10(8) {h}(-2) {M_sun}at 23 {h}(-1) Mpc and to M_HI = 4-8x10(7) {h}(-2) {M_sun} throughout theCVn groups. The survey region had been previously examined on deepoptical plates by \cite[Binggeli et al. (1990)]{bin90} and containsloose groups with many gas-rich galaxies as well as voids. No galaxiesthat had not been previously identified in these deep optical surveyswere uncovered in our H{sigma c i} survey, neither in the groups nor thevoids. The implication is that no substantial quantity of neutralhydrogen contained in gas-rich galaxies has been missed in thesewell-studied groups. All late-type members of our sample are listed inthe \cite[Fisher & Tully (1981b)]{fis81b} optically selected sampleof nearby late-type galaxies; the only system not contained in Fisherand Tully's Catalog is the S0 galaxy NGC 4203. Within the well-sampledCVn group volume with distances corrected for flow motions, the H {sigmac i} mass function is best fitted with the \cite[Zwaan et al.(1997)]{zwa97} H{sigma c i} mass function (alpha =-1.2) scaled by afactor of f=4.5 in account of the locally overdense region.
| The Absence of X-Ray Flashes from Nearby Galaxies and the Gamma-Ray Burst Distance Scale
If typical gamma-ray bursts (GRBs) have X-ray counterparts similar tothose detected by Ginga, then sensitive-focusing X-ray telescopes willbe able to detect GRBs 3 orders of magnitude fainter than the detectionlimit of the Burst and Transient Source Experiment (BATSE). If asubstantial portion of the burst population detected by BATSE originatesin a Galactic halo at distances greater than or equal to 150 kpc,existing X-ray telescopes will be able to detect GRBs in externalgalaxies out to a distance of at least 4.5 Mpc. As reported in Gotthelf,Hamilton, & Helfand, the imaging proportional counter (IPC) on boardthe Einstein Observatory detected 42 transient events with pointlikespatial characteristics and timescales of less than 10 s. These eventsare distributed isotropically on the sky; in particular, they are notconcentrated in the directions of nearby external galaxies. For halomodels of the BATSE bursts with radii of 150 kpc or greater, we wouldexpect to see several burst events in observations pointed toward nearbygalaxies. We see none. We therefore conclude that if the Gingadetections are representative of the population of GRBs sampled byBATSE, GRBs cannot originate in a Galactic halo population with limitingradii between 150 and 400 kpc. Inasmuch as halos with limiting radiioutside of this range have been excluded by the BATSE isotropymeasurements, our result indicates that all halo models are excluded.This result is independent of whether the flashes we do detect have anastronomical origin.
| Statistical correlations between basic parameters of disk galaxies
Statistical relationships between principal galaxy parameters andsurface densities of these parameters are analyzed for a sample of 63disk galaxies. These parameters include the radius, the mass of theentire galaxy and its various components (H2, HI, total gas, dust,etc.), and blue and FIR luminosity. Of all possible two- andthree-parameter linear relations between the galaxy parameterlogarithms, we choose those that have high correlation coefficients andproceed to derive their coefficients. Some of these relations arecompared with the corresponding predictions of the single-zone model ofthe disk galaxy evolution. Other relations are considered from theviewpoint of interstellar medium properties in galaxies. We find thetheory to agree satisfactorily with observations and suggest ways ofimproving evolutionary models. The method of linear orthogonalregression used in the statistical analysis is described.
| The orientation of spin vectors of galaxies in the Ursa Major filament
Spin vectors of 60 galaxies in the 'Ursa Major filament' are obtainedfrom CCD images and spectroscopic determinations of the directions ofrotation. These data are used to remove the fourfold degeneracyintroduced by the projected images of galaxies, making possible thecomplete reconstruction of the galaxy spin vectors. Several possibleorganizations of spin vectors are investigated by means of statisticalanalyses of the three-dimensional spin vector maps. The results indicatethat there exists no significant alignment of galaxy spin vectors withrespect to the supergalactic plane, the supergalactic axis, or thecylindrical axis of the filament itself. No tendency for linearalignment of spin vectors toward any specific direction was detected. Wealso obtain a statistically negative result for azimuthal, radial, andcircular-helical orientation of spin vectors.
| Arm structure in normal spiral galaxies, 1: Multivariate data for 492 galaxies
Multivariate data have been collected as part of an effort to develop anew classification system for spiral galaxies, one which is notnecessarily based on subjective morphological properties. A sample of492 moderately bright northern Sa and Sc spirals was chosen for futurestatistical analysis. New observations were made at 20 and 21 cm; thelatter data are described in detail here. Infrared Astronomy Satellite(IRAS) fluxes were obtained from archival data. Finally, new estimatesof arm pattern radomness and of local environmental harshness werecompiled for most sample objects.
| H I deficiency in the Coma I cloud of galaxies
We present new H I observations of galaxies in the Coma I group. Of the32 most probable members of the group, 16 are gas poor and 16 havenormal H I contents. The 16 gas poor galaxies include 4 ellipticals, 5S0s, and 7 spirals with a definite H I deficiency (more than a factor offour). Most of the 16 gas poor or H I deficient galaxies areconcentrated within a radius of 500 kpc of a centroid near the galaxyNGC 4274, suggesting that this region contains a compact core ofintergalactic matter that has stripped the gas from some of thegalaxies. Seven gas poor galaxies are even within a projected radius of130 kpc of this position. This possible existence of a dense core ofintragroup gas may explain the large H I deficiency in the barred spiralNGC 4314. which has 100 times less H I mass than would be expected fromits luminosity and stellar mass. In this galaxy the gas is 99%molecular, 1% atomic and nearly all in the central region. We suspectthe extreme H I deficiency in NGC 4314 is due to two distinct causes:ram pressure stripping of the gas in its outer parts, plus action of itsbar or an ancient tidal interaction with another galaxy that transferredgas from the inner parts of NGC 4314 to the center where H I wasconverted to H_2_.
| A revised catalog of CfA1 galaxy groups in the Virgo/Great Attractor flow field
A new identification of groups and clusters in the CfA1 Catalog ofHuchra et al. is presented, using a percolation algorithm to identifydensity enhancements. It is shown that in the resulting catalog,contamination by interlopers is significantly reduced. The Schechterluminosity function is redetermined, including the Malmquist bias.
| Molecular gas in nearby galaxies. II - The data
The study reports observations of (C-12)O J = 1-0 emission from 50nearby spiral galaxies. This is part of a distance-limited survey ofnearby systems which are not strongly interacting with their neighbors.The observations were performed during December 1988 and March 1990using the NRAO 12-m telescope at Kitt Peak with the 3-mm SIS receiversand the 256-channel x 2-MHz spectrometers.
| 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.
| Molecular Gas in Nearby Galaxies - Part One - Co/ Observations of a Distance-Limited Sample
This paper presents a discussion of ^12^CO J = 1 - 0 observations of adistance-limited sample of nearby spiral galaxies. The sample is biasedtowards high inclination galaxies at the lowest blue luminosities,suggesting a systematic effect. Two possible explanations are brieflydiscussed. The bias may be an artifact of the way Hubble types areassigned to galaxies or axis ratios measured, or it may indicate ameasurable effect of the local supercluster on lower mass galaxies. Themolecular mass is a relatively constant fraction (~2%) of the dynamicalmass within the region containing H_2_, but varies when the totaldynamical mass is considered (assuming a constant CO to H_2_ conversionfactor for all galaxies in the sample). The ratio of M(H_2_)/M_dyn_ isindependent of Hubble type. M(H_2_)/M(HI) is a strong function of Hubbletype, but this arises entirely because of the dependence of atomic masson type. The molecular masses and FIR luminosities are well correlated,but the average ratio of L_FIR_ to M(H_2_) is only ~1/2 that of previousstudies, which were based on (primarily) FIR selected samples. Thissuggests that the efficiency of star formation in a normal spiral galaxyis lower than that estimated by previous studies.
| 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.
| 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.
| Groups of galaxies in the Center for Astrophysics redshift survey
By applying the Huchra and Geller (1982) objective group identificationalgorithm to the Center for Astrophysics' redshift survey, a catalog of128 groups with three or more members is extracted, and 92 of these areused as a statistical sample. A comparison of the distribution of groupcenters with the distribution of all galaxies in the survey indicatesqualitatively that groups trace the large-scale structure of the region.The physical properties of groups may be related to the details oflarge-scale structure, and it is concluded that differences among groupcatalogs may be due to the properties of large-scale structures andtheir location relative to the survey limits.
| 21 centimeter study of spiral galaxies in the Coma supercluster
High-sensitivity, 21 cm line observations of 130 galaxies in theComa/A1367 Supercluster region are presented and used to study thelarge-scale distribution of galaxies in the direction of the ComaSupercluster and the H I content in spiral galaxies as a function of thelocal galaxy density. Groups of galaxies are found to form aquasi-continuous structure that connects the Local Supercluster to theComa Supercluster. This structure is composed of real filaments only inthe vicinity of the Coma Cluster. Spiral galaxies in the surveyed groupsand multiple systems have H I content not dissimilar from that ofisolated galaxies. Galaxies within about 1 Abell radius from the ComaCluster contain about three times less hydrogen on average than isolatedgalaxies. There is a strong tendency for galaxies that are more severelyH I-depleted to be redder and of earlier Hubble type. In the ComaCluster a considerable fraction of late-type, blue galaxies have largedeficiency parameters.
| The spatial distribution of dwarf galaxies in the CfA slice of the universe
A complete (with the the exception of one) redshift sample of 58galaxies in the Nilson catalog classified as dwarf, irregular, orMagellanic irregular is used to investigate the large-scale clusteringproperties of these low-surface brightness galaxies in the CfA slice ofthe universe (alpha in the range of 8-17 h, delta in the range of26.5-32.5 deg). It is found that the low-surface brightness dwarfgalaxies also lie on the structures delineated by the high-surfacebrightness normal galaxies and that they do not fill in the voids. Thisis inconsistent with a class of biased galaxy formation theories whichpredict that dwarf galaxies should be present everywhere, including thevoids.
| H I line studies of galaxies. IV - Distance moduli of 468 disk galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...43B&db_key=AST
| 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.
| Extragalactic nebulae.
This contribution gives the results of a statistical investigation of400 extragalactic nebulae for which Holetschek has determined totalvisual magnitudes. The list is complete for the brighter nebulae in thenorthern sky and is representative to 12.5 mag. or fainter. Theclassification employed is based on the forms of the photographicimages. About 3 per cent are irregular, but the remaining nebulae fallinto a sequence of type forms characterized by rotational symmetry aboutdominating nuclei. The sequence is composed of two sections, theelliptical nebulae and the spirals, which merge into each other.Luminosity relations. - The distribution of magnitudes appears to beuniform throughout the sequence. For each type or stage in the sequence,the total magnitudes are related to the logarithms of the maximumdiameters by the formula, mT = C - 5 log d, where C variesprogressively from type to type, indicating a variation in diameter fora given magnitude or vice versa. By applying corrections to C, thenebulae can be reduced to a standard type and then a single formulaexpresses the relation for all nebulae from the Magellanic Clouds to thefaintest that can be classified. When the minor diameter is used, thevalue of C is approximately constant throughout the entire sequence. Thecoefficient of log d corresponds with the inverse-square law, whichsuggests that the nebulae are all of the same order of absoluteluminosity and that apparent magnitudes are measures of distance. Thishypothesis is supported by similar results for the nuclear magnitudesand the magnitudes of the brightest stars involved, and by the smallrange in luminosities among nebulae whose distances are already known.Distances and absolute dimensions. - The mean absolute visual magnitude,as derived from the nebulae whose distances are known, is -15.2. Thestatistical expression for the distance in parsecs is then log D = 4.04+ 0.2 mT. where mT is the total apparentmagnitude. This leads to mean values for absolute dimensions at variousstages in the sequence of types. Masses appear to be of the order of2.6x108 Msun. Distribution and density of space. -To apparent magnitude about 16.7, corresponding to an exposure of onehour on fast plates with the 60-inch reflector, the numbers of nebulaeto various limits of total magnitude vary directly with the volumes ofspace represented by the limits. This indicates an approximately uniformdensity of space, of the order of one nebula per 1017 cubicparsecs or 1.5x10-31 in C.G.S. units. The correspondingradius of curvature of the finite universe of general relativity is ofthe order of 2.7x1010 parsecs, or about 600 times thedistance at which normal nebulae can be detected with the 100-inchreflector.
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