Gas and Stars in an H I-Selected Galaxy Sample
We present the results of a J-band study of the H I-selected AreciboDual-Beam Survey and Arecibo Slice Survey galaxy samples using TwoMicron All Sky Survey data. We find that these galaxies span a widerange of stellar and gas properties. However, despite the diversitywithin the samples, we find a very tight correlation between luminosityand size in the J band, similar to that found in a previous paper byRosenberg & Schneider between the H I mass and size. We also findthat the correlation between the baryonic mass and the J-band diameteris even tighter than that between the baryonic mass and the rotationalvelocity.
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Redshift-Distance Survey of Early-Type Galaxies: Spectroscopic Data
We present central velocity dispersions and Mg2 line indicesfor an all-sky sample of ~1178 elliptical and S0 galaxies, of which 984had no previous measures. This sample contains the largest set ofhomogeneous spectroscopic data for a uniform sample of ellipticalgalaxies in the nearby universe. These galaxies were observed as part ofthe ENEAR project, designed to study the peculiar motions and internalproperties of the local early-type galaxies. Using 523 repeatedobservations of 317 galaxies obtained during different runs, the dataare brought to a common zero point. These multiple observations, takenduring the many runs and different instrumental setups employed for thisproject, are used to derive statistical corrections to the data and arefound to be relatively small, typically <~5% of the velocitydispersion and 0.01 mag in the Mg2 line strength. Typicalerrors are about 8% in velocity dispersion and 0.01 mag inMg2, in good agreement with values published elsewhere.
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Redshift-Distance Survey of Early-Type Galaxies: Circular-Aperture Photometry
We present R-band CCD photometry for 1332 early-type galaxies, observedas part of the ENEAR survey of peculiar motions using early-typegalaxies in the nearby universe. Circular apertures are used to tracethe surface brightness profiles, which are then fitted by atwo-component bulge-disk model. From the fits, we obtain the structuralparameters required to estimate galaxy distances using theDn-σ and fundamental plane relations. We find thatabout 12% of the galaxies are well represented by a pure r1/4law, while 87% are best fitted by a two-component model. There are 356repeated observations of 257 galaxies obtained during different runsthat are used to derive statistical corrections and bring the data to acommon system. We also use these repeated observations to estimate ourinternal errors. The accuracy of our measurements are tested by thecomparison of 354 galaxies in common with other authors. Typical errorsin our measurements are 0.011 dex for logDn, 0.064 dex forlogre, 0.086 mag arcsec-2 for<μe>, and 0.09 for mRC,comparable to those estimated by other authors. The photometric datareported here represent one of the largest high-quality and uniformall-sky samples currently available for early-type galaxies in thenearby universe, especially suitable for peculiar motion studies.Based on observations at Cerro Tololo Inter-American Observatory (CTIO),National Optical Astronomy Observatory, which is operated by theAssociation of Universities for Research in Astronomy, Inc., undercooperative agreement with the National Science Foundation (NSF);European Southern Observatory (ESO); Fred Lawrence Whipple Observatory(FLWO); and the MDM Observatory on Kitt Peak.
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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
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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.
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A Deep Survey of H I-selected Galaxies: The Sample and the Data
In a 21 cm neutral hydrogen survey of approximately 55 deg^2 out to aredshift of cz = 8340 km s^-1, we have identified 75 extragalactic H Isources. These objects comprise a well-defined sample of extragalacticsources chosen by means that are independent of optical surfacebrightness selection effects. In this paper we describe the Arecibosurvey procedures and H I data, follow-up VLA H I observations made ofseveral unusual sources, and Kitt Peak B-, R-, and I-band photometry fornearly all of the galaxies. We have also gathered information for someof the optically detected galaxies within the same search volume. Weexamine how samples generated by different types of search techniquesoverlap with selection by H I flux. Only the least massive H I object,which is among the lowest mass H I sources previously found, does nothave a clear optical counterpart, but a nearby bright star may hide lowsurface brightness emission. However, the newly detected systems do haveunusual optical properties. Most of the 40 galaxies that were notpreviously identified in magnitude-limited catalogs appear to begas-dominated systems, and several of these systems have H Imass-to-light ratios among the largest values ever previously found.These gas-dominated objects also tend to have very blue colors, lowsurface brightnesses, and no central bulges, which correlate stronglywith their relative star-to-gas content.
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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
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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.
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On the question of radio emission of spiral galaxies in groups of galaxies
It has been shown that the radio emission properties of spiral galaxies,if the other conditions are the same, are determined rather by thepresence of the close neighbours than by space density of galaxiesaround them. The rate of occurence of radio sources and their radioluminosities among the spiral members of groups of galaxies depend onthe projected seperation between them and their nearest neighbour. Theshorter this seperation the higher the probability of radio emission.
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Star formation in the disks of H I-rich S0 galaxies
We present the results of a H-alpha emission-line imaging survey of asample of neutral-gas-rich S galaxies. We find evidence of disk H IIregions in 14 of our sample of 32 galaxies, detect nuclear or faintdiffuse circumnuclear H-alpha + forbidden N II emission in another 11galaxies without disk H II regions, and obtain upper limits for 8galaxies. We find a striking dichotomy between Ss with and without H IIregions; either a galaxy has a number of H II regions, most oftendistributed into distinct rings or ringlike structures, or there arenone down to detection limits equivalent to a single unreddened H IIregion ionized by single O stars. We find that the S0s without disk H IIregions have a lower median MH I/L(B) than those with disk HII regions, but the distributions have a large range of dispersion. Ourdata suggest that S0s may lie in a regime where local threshold effects,perhaps primarily kinematic in origin, are more important in determiningthe star formation in these galaxies than the global stabilitymechanisms that recent empirical models for large-scale star formationhave suggested prevail in later-type spirals.
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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.
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H I content and FIR emission of S0 galaxies
A sample of 252 S0 galaxies is used to study the relationship between HI content and far-IR emission. Logarithms of the H I content versus thefar-IR emission are employed statistically to develop a best-fit linearregression line which is compared to a slope of approximately unity. Theslopes are different for S0 and SB0 galaxies versus S0/a and SB0/agalaxies. The distribution of the 60-100 micron flux ratio is notsignificantly affected by the presence or absence of bars nor by thedifferences between the S0 and S0/a systems. The flux ratio is higherthan the critical value of Helou in 34 percent of the cases, and thevalue holds when nuclear emission is taken into account. In cases wherethe critical value is exceeded, most far-IR emissions are expected to bedue to star formation. S0 galaxies are generally found to have a normalISM, except where the systems have accreted their H I gas. Systems withdisproportionate FIR emission can be considered galaxies that areexperiencing enhanced star formation or that have had their H I gasswept away.
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Star formation in spiral galaxies. I - H-alpha observations
This paper presents large-aperture photometric measurements of H-alpha +forbidden N II emission line strengths in 110 spiral galaxies. Thesegalaxies represent three different samples of objects: (1) low surfacebrightness spiral galaxies; (2) galaxies of extreme arm classifications(flocculent versus grand design); and (3) galaxies with measured (B -H)colors which have been used to study the color-absolute magnituderelation for spiral galaxies. Details of the observations are given, anda comparison is made with previous work. Future papers will use thisdata to study the star-formation rates in the various samples.
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Periodicities in galaxy redshifts
Using new data for unassociated galaxies with wide H I profiles andvalues of period and solar motion predicted by Tifft and Cocke (1984), aperiodicity has been found which is significant at the conventional 5percent level. Together with Tifft's work on galaxy pairs and smallgroups, this result appears to provide evidence in favor of thehypothesis that measured galaxy redshifts occur in steps of a littlemore than 72 km/s or a simple multiple of this period.
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Observations of galaxies in groups at 102 MHz
Observations of 325 galaxies in groups were carried out at a frequencyof 102 MHz via the scintillation method. Radio emission was found in 42of these components. Eleven of these have a meridional component.
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Large-scale structure of the Hercules supercluster.
Not Available
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H I observations of lenticular and early type galaxies
High sensitivity H I observations of 56 galaxies, mostly S0's (47objects), carried out with the Arecibo radio telescope are presented.Twelve S0's and four S0/a spirals have been detected, among which 12 forthe first time, and nine of them have been mapped. In addition,absorption lines have been found in two S0's. A detailed discussion ofthe results of the mapping has made it possible to solve several casesof confusion and to find out two possible cases of H I ring structuresor flat rotation curves in S0's. Finally for six mapped galaxies, asimple deconvolution procedure has led to the derivation of the total HI fluxes and of the H I diameters; on the average, the ratio of the H Idiameter to the optical one is found to be 30 percent higher for theS0's than for the spirals.
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Neutral hydrogen in small groups of galaxies
Neutral hydrogen in 36 pairs and small groups of galaxies was studiedusing the Arecibo radio telescope. Potential groups were selected fromthe Uppsala General Catalogue of Galaxies of Nilson (1973) by a simplealgorithm with the aims of determining or improving redshifts forgalaxies in possible groups and of mapping some of the larger galaxiesto determine their internal dynamics. The H I spectra are examined indetail and problems of confusion in these and previous observations areaddressed. A simple analysis of the groups' mean dynamical mass suggeststhat the mass determined from the galaxies' rotation is sufficient tobind them, but there may be important unmodeled selection orcontamination problems. A simple method for estimating errors of H Ivelocity measurements is also derived.
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A 21 CM survey of the Pisces-Perseus supercluster. II - The declination zone +21.5 to +27.5 degrees
Neutral-hydrogen 21-cm line spectra and derived parameters are presentedfor a sample of spiral galaxies in the region bounded by an R.A. greaterthan 22 h and less then 0.04 h, and a declination greater than +21 deg30 min and less than +27 deg 30 min, covering the Zwicky fields 470 to488, as the second installment of a survey of the region of thePisces-Perseus supercluster. New H I line observations made with theArecibo 305 m telescope detected 275 galaxies of 318 studied. Atabulation of derived galaxian properties is given. The redshiftdistribution shows gross departures from that expected for a sample withsimilar magnitude characteristics but homogeneously located in space.These new data will be incorporated into the overall survey of thethree-dimensional structure in the Pisces-Perseus region.
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The statistical distribution of the neutral-hydrogen content of S0 galaxies
The distribution of relative global H I content M(H I)/L(B) has beenderived for galaxies of types S0 and S0/a using a data set derived fromrecent H I observations in the literature. The relative H I content ofthese galaxies is found to show transitional properties betweenelliptical and spiral galaxies. The distribution of M(H I)/L(B) forS0/a's resembles that for spirals, and these galaxies may represent'fossil' spirals, i.e., galaxies whose gas has been severely depleted bystar formation. The distribution for S0's, however, resembles that forellipticals. The form of this distribution strongly suggests an externalorigin for most of the H I in S0 galaxies.
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A catalog of 2810 nearby galaxies - The effect of the Virgocentric flow model on their observed velocities
A catalog of 2810 nearby galaxies is constructed on the basis of threesubcatalogs: galaxies with B(T) less than or equal to 13.4 mag, galaxieswith v0 less than or equal to 500 km/s, and galaxies having B(T) lessthan or equal to 14.95 mag and lying within a 10-deg cone around M87.The data are compiled in tables and graphs and characterized in detail.The distances to objects with known red shifts are determined in unitsof the Virgo-cluster distance, independent of H0, using two versions ofthe nonlinear Virgocentric-flow models of Silk (1974 and 1977) and shownto correspond to local Virgo-inflow rates of 220 and 440 km/s,respectively. The luminous-galaxy distribution is described as acell-like structure with several superclusters, chains ofinterconnecting galaxies, and large voids.
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The H I content of lenticular and early-type galaxies - A comparison between field and Virgo cluster samples
A very simple method to take into account the upper limits of detectionis used to study and discuss the distribution of the H I contents of 122lenticular galaxies. The results show the Virgo cluster S0s to be H Ideficient when compared to the noncluster ones, and the H I contents ofthe latter to be about five times lower than the ones of the S0/aspirals and to increase along the de Vaucouleurs sequence of types -3 to-1. It is shown that the early spirals in Virgo are H I-deficient by afactor higher than 10, i.e., they have no more gas than noncluster S0s.It is argued that noncluster S0s have a primordial origin, and that asubstantial proportion of Virgo S0s come from stripped early spirals.
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A search for environmental effects on the optical properties of galaxies in groups
Environmental density-related modifications of basic optical properties(luminosities, sizes, axial ratios, and colors) of galaxies belonging toGeller and Huchra's (1983) groups have been investigated. Remarkably, itis found that the broad maxima of the distributions of luminosities anddiameters of spirals and the whole corresponding distributions oflenticulars tend to move to lower values as one goes to groups of highcompactness, whereas the luminosity-diameter relationship of spiralstends to become flatter. No color and axial ratio differences betweengalaxies of high- and low-compactness groups have been detected.
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A comparison of distance scales for early-type galaxies
The distance scales of elliptical and lenticular galaxies areintercompared, based on the velocity dispersion indicator derived from arevised Faber-Jackson relation. The scales are found to be in nearperfect agreement with scales derived from the luminosity index and fromthe 21 cm line width indicator. The scales are also in excellentagreement with the distance scale derived by Michard (1979). Additionsare offered for the general catalog of 424 early-type galaxies, and aseries of reduction equations is presented which reduces the externalerrors in the distance moduli.
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Enhanced radio emission in binary spiral galaxies
A comparison is conducted between the radio emission characteristics ofa sample of isolated pairs of spiral galaxies and those of a sample ofisolated spiral galaxies for which complete distance information isavailable. It is noted that double galaxy total emission is, on average,a factor of 2 more powerful than that of isolated spiral galaxies ofcomparable luminosity. The radio emission enhancement in these doublegalaxies is correlated with a tidal index, in keeping with a tidalorigin for the enhancement.
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Very large spiral galaxies
As a first step in the systematic study of large spirals, which may beuseful in cosmological tests and studies of galaxy evolution, a catalogof the 107 largest known spiral galaxies is presented. Catalog galaxieshave isophotal diameters greater than 90 kpc, assuming an H(zero) valueof 50 km/sec per Mpc. UBVR photoelectric photometry is presented for 20of these galaxies, and absolute magnitudes are derived for all galaxiesin the catalog by transforming Zwicky magnitudes to the B(T) system.
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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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Groups of galaxies. III - The CfA survey
A statistically homogeneous group catalog (CfA) is based on the CfAredshift survey (Huchra et al.) is presented. Groups in the catalog areall density enhancements in redshift space of a factor greater than 20.Group members are identified according to the procedure described in aprevious study (Huchra and Geller) of a shallower whole-sky sample. Allgroups contain at least three members. Of the 176 groups in the CfAcatalog, 102 have been identified in one or more previous studies.Because the utilized algorithm searches for volume rather than surfacedensity enhancements, the groups in a given region generally change onlythrough the addition of fainter members when the magnitude limit of thegalaxy catalog increases. In the region of overlap, agreement betweenthe shallow catalog and the CfA catalog is excellent.
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Radio observations of galaxies of the Byurakan classification at 102 MHz
Interplanetary-scintillation observations at 102 MHz have been made of131 galaxies of the Biurakan classification (1975). It is found thatgalaxies with more pronounced nuclei have higher activity in the radiorange and that scintillating components (with angular dimensions about0.1 arcsec) are more frequently found in them. The scintillatingcomponents have steep spectra.
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21-cm line observations of 59 lenticular and spiral galaxies
Fifty-nine lenticular and spiral galaxies have been observed with theNancay Radiotelescope. Forty-one have been detected and for nine objectsdetected in more than one position the HI diameter is given. Thecomparison between HI fluxes observed with the Nancay Radiotelescope andthose obtained with other radiotelescopes shows a good generalagreement, implying an uncertainty on the HI flux measurements about 3Jy-km/s, whereas the few obvious disagreements observed are due toconfusion or to anomalous HI extensions.
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