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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
| 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.
| On the Influence of the Environment on the Star Formation Rates of a Sample of Galaxies in Nearby Compact Groups
We present the results of a study of the star formation rates (SFRs) ofa sample of disk galaxies in nearby compact groups compared with theSFRs of a sample of field galaxies. For this purpose, Hαluminosities and equivalent widths were derived for the galaxies of oursample. A direct comparison of the equivalent widths and Hαluminosities, normalized to the B luminosities and estimated area of thegalaxies of both samples, yields the result that the median values ofthese quantities are almost identical for both samples, although thedistributions for the compact-group sample are broader around the meanvalue than was found in the field galaxy sample. This result can beexplained by assuming that although interactions between galaxies incompact groups can alter the SFRs, the median value of the normalizedSFRs is preserved, being almost indistinguishable from the correspondingvalue for field galaxies. Measuring the global L_Hα/L_B of thegroups, including early-type galaxies, we find that most of the groupsthat show the highest level of L_Hα/L_B with respect to a set ofsynthetic groups built out of field galaxies show tidal features in atleast one of their members. Finally, we have explored the relationshipbetween the ratio L_Hα/L_B and several relevant dynamicalparameters of the groups: velocity dispersion, crossing time, radius,and the mass-to-luminosity ratio, finding no clear correlation. Thissuggests that the exact dynamical state of a group does not control theSFR of the group as a whole. Our results are compatible with a scenariofor compact groups of galaxies in which the dark matter of the group isarranged in a common halo, therefore preventing a fast collapse of thegalaxies.
| Disk Galaxies in the Outer Local Supercluster: Optical CCD Surface Photometry and Distribution of Galaxy Disk Parameters
We report new B-band CCD surface photometry on a sample of 76 diskgalaxies brighter than B_T = 14.5 mag in the Uppsala General Catalogueof Galaxies that are confined within a volume located in the outer partof the Local Supercluster. With our earlier published I-band CCD andhigh signal-to-noise ratio 21 cm H I data, this paper completes ouroptical surface photometry campaign on this galaxy sample. As anapplication of this data set, the B-band photometry is used here toillustrate two selection effects that have been somewhat overlooked inthe literature but that may be important in deriving the distributionfunction of disk central surface brightness (CSB) of disk galaxies froma diameter- and/or flux-limited sample: a Malmquist-type bias againstdisk galaxies with small disk scale lengths (DSLs) at a given CSB and adisk inclination-dependent selection effect that may, for example, biastoward inclined disks near the threshold of a diameter-limited selectionif disks are not completely opaque in the optical. Taking intoconsideration these selection effects, we present a method ofconstructing a volume-sampling function and a way to interpret thederived distribution function of CSB and DSL. Application of this methodto our galaxy sample implies that if galaxy disks are optically thin,CSB and DSL may well be correlated in the sense that, up to aninclination-corrected limiting CSB of about 24.5 mag arcsec^-2 that isadequately probed by our galaxy sample, the DSL distribution of galaxieswith a lower CSB may have a longer tail toward large values unless thedistribution of disk galaxies as a function of CSB rises rapidly towardfaint values.
| 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 image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
| The FCRAO Extragalactic CO Survey. I. The Data
Emission from the CO molecule at λ = 2.6 mm has been observed at1412 positions in 300 galaxies using the 14 m telescope of the FiveCollege Radio Astronomy Observatory (HPBW = 45"); these data comprisethe FCRAO Extragalactic CO Survey. In this paper we describe the galaxysample, present the data, and determine global CO fluxes and radialdistributions for the galaxies in the Survey. Future papers will dealwith the data analysis, both with regard to the global properties ofgalaxies and the radial distributions within them. CO emission wasdetected in 236 of the 300 Survey galaxies for an overall detection rateof 79%; among the 52 Sc galaxies in the Survey, the detection rate wasas high as 96%. most of the 193 galaxies observed in multiple positionsexhibit CO distributions which peak at the center. However, a smallnumber (10-primarily Sb galaxies) exhibit CO rings at 45" resolution,and a similar number (18-primarily Sc galaxies) have CO distributionswhich peak on one side of the center. We derive CO isophotal diametersfor 151 galaxies and find the mean ratio of CO to optical isophotaldiameters to be 0.5. We also find a trend along the Hubble sequence suchthat the mean ratio of CO to optical isophotal diameters is smallestamong the early-type spirals (SO/a, Sa, and Sab) and the mean ratioincreases for Sb, Sbc, and Sc galaxies, finally decreasing among thelater types. Comparison of the global fluxes we derive for the Surveygalaxies with independent measurements from the literature indicatesthat the global fluxes we derive are accurate to ~40%.
| Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
| Global properties of dwarf galaxies II. Colours and luminosities
We have used a previously determined sample of 278 dwarf galaxies formost of which B magnitudes, optical colours, HI fluxes and IRASflux-densities are known, in order to derive luminosities, colours andsurface brightnesses. Dwarf galaxy properties are compared to those of acontrol sample of 228 larger spiral galaxies. The dwarf galaxies have onaverage higher 60/100μm flux ratios and lower 12/25μm flux ratiosthan the spiral galaxies, indicating that the contribution of `cirrus'to the infrared emission from dwarf galaxies is relativelyinsignificant. In the dwarf galaxies, the 60/100μm flux ratioincreases with increasing optical blueness; spiral galaxies show theopposite. Dwarf galaxies with a low optical surface brightness have low100μm/HI ratios, but the converse is not true. Galaxies with high100μm/HI ratios (indicative of high dust-to-gas ratios) also havehigh FIR/B ratios as well as high 60/100μm flux-density ratios.Although this is true for both spiral and dwarf galaxies, at given100μm/HI ratios the dwarf galaxies have both a lower FIR/B ratio anda higher 60/100μm flux-density ratio. This result is of importance inthe interpretation of FIR/B - 60/100μm diagrams in terms of starformation activity.
| Global properties of dwarf galaxies. I. Galaxy sample and IRAS infrared flux-densities
We have selected a sample of 278 dwarf galaxies for which at least Bmagnitudes and preferably also optical colour information are available.For those galaxies that have no previously published IRAS fluxes, wehave used the IRAS database to extract fluxes or upper limits tosensitivity levels significantly better than those of the IRAS PointSource Catalog. New IRAS data include 79 galaxies detected in at leastone band, and 66 galaxies with good upper limits. In total, about 60% ofall dwarf galaxies in the sample now have been detected at 60/100μm.
| H I 21 centimeter observations and I-band CCD surface photometry of spiral galaxies behind the Virgo Cluster and toward its antipode
Sample selection, radio and optical data acquisition and reduction, andobservation results are presented for spiral galaxies behind the VirgoCluster and toward its antipode. I-band CCD photometry was obtained forall the bright galaxies and part of the sample of faint galaxies in thetwo local volumes was studied. The statistical properties of the galaxysamples are discussed.
| A survey of the Pisces-Perseus supercluster. VI - The declination zone +15.5 deg to 21.5 deg
New results are presented of Arecibo observations in the 21 cm line of765 galaxies with declinations between 15.5 deg and 21.5 deg, in thePisces-Perseus supercluster zone. If considered independently on theneighboring parts of sky, this region, to the South of the superclusterridge, shows significantly less evidence of structure on large scales inexcess of 30 Mpc, contrasting substantially with the characteristics ofthe declination zones immediately to the North.
| IRAS observations of H-alpha selected emission-line galaxies
We present the results of IRAS observations of the UCM (UniversidadComplutense de Madrid) sample of emission-line galaxies, which have beenselected from wide-dispersion H-alpha objective-prism plates. These dataare intended to provide a convenient summary of the relevant FIRproperties of these galaxies. Color-color diagrams, as interpreted bytheoretical models, suggest that emission from UCM galaxies is mainlydue to dust heated directly by photons emitted in active star-formingregions. Statistical analysis of some samples, including the IRASminisurvey and blue-selected objective-prism samples, have beenperformed. Comparisons, based on FIR luminosity distributions, with theIRAS minisurvey make evident the lower metallicity of the CUM galaxieswhich cannot be considered as a parent population of IRAS-detectedgalaxies.
| H2O masers in nearby irregular galaxies
The results of a search for luminous interstellar H2O masers in 15nearby irregular galaxies are presented. One new maser was detected inthe Magellanic-type irregular galaxy IC 10. It was observed six timesbetween 1987 and 1990 and did not exhibit flux density variationsexceeding a factor of three. The newly discovered maser is located 2arcmin to the north of another, more luminous H2O maser source, whichhas been monitored over a time interval of six years. The position ofthe v(LSR)= -332 km/s component of the more luminous maser wasdetermined to an accuracy of about 2 arcsec. This component wasundergoing a 'slow' burst during 1985 and most of 1986, with thelinewidth varying as the -1/3 power of the flux density. In 1990, astrong burst was observed in the v(LSR)= -324 km/s component, whichreached a flux density of 31 Jy. For this component the linewidth-fluxdensity relation is the same within the uncertainty limits.
| 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.
| A self-regulated star formation rate as a function of global galactic parameters
A sample of active dwarf galaxies and a sample of Sc and irregulargalaxies are analyzed based on the assumption that the stellar formationrate is self-regulated in such a way that it maintains the criticalpressure P(max) near the gas pressure P(g) of the interstellar medium,where P(max) is the pressure of the marginal state of stability for thetransition warm gas to small clouds. The stellar formation rate Psi(PP)consistent with the condition P(max) = P(g), can be expressed as asimple analytical function of global galactic parameters. When it isassumed that the dust temperature, the gas metallicity, and the galacticdiameter remain constant, it is found that Psi(PP) is reduced to the lawof Schmidt with an exponent value of 1.43. Specifically, for the Galaxy,it is fond that Psi(PP) = about 10 solar masses/yr, which is reasonablyconsistent with previous values.
| Global properties of infrared bright galaxies
Infrared flux densities of 182 galaxies, including 50 galaxies in theVirgo cluster, were analyzed using IRAS data for 12, 25, 60, and 100microns, and the results were compared with data listed in the PointSource Catalog (PSC, 1985). In addition, IR luminosities, L(IRs),colors, and warm dust masses were derived for these galaxies and werecompared with the interstellar gas masses and optical luminosities ofthe galaxies. It was found that, for galaxies whose optical diametermeasures between 5 and 8 arcmin, the PSC flux densities areunderestimated by a factor of 2 at 60 microns, and by a factor of 1.5 at100 microns. It was also found that, for 49 galaxies, the mass of warmdust correlated well with the H2 mass, and that L(IR) correlated withL(H-alpha), demonstrating that the L(IR) measures the rate of starformation in these galaxies.
| Star-formation rates and forbidden O II emission in blue galaxies
Observations of forbidden O II 3727 A and H-beta emission-line strengthsare presented from large-aperture spectrophotometric observations ofnearby (z less than 0.1) optically blue galaxies covering a wide rangein surface brightness and luminosity. The forbidden O II emission-lineequivalent widths in these galaxies primarily lie between 30 and 100 A.Emission-line strengths in nearby blue galaxies thus resemble thosefound in faint galaxies at moderate-to-high redshifts. The most activelystar-forming nearby galaxies are characterized by surface brightness inthe forbidden O II line of about 10 to the -15th to 10 to the -14thergs/s per sq cm per sq arcsec over spatial distances of more than 1kpc. The fluxes of the forbidden O II and H-beta emission lines are wellcorrelated, and thus forbidden O II luminosities can be used to deriveapproximate star-formation rates in blue galaxies.
| IRAS observations of a large sample of normal irregular galaxies
IRAS 12, 25, 60, and 100 micron data are presented for a sample of Irrgalaxies which span a large range in star-formation activity. It isfound that the dwarf, giant, and amorphous Irr's generally have similarIR properties. The typical L(IR)/L(H-alpha) ratios of most classes ofIrr's, except for many of the luminous blue galaxies, are low comparedwith those of spiral galaxies and are consistent with the Irr's beingrelatively transparent systems without large amounts of optically hiddenstar formation. Compared with spiral galaxies, the Irr's have similarL(IR)/L(B) ratios, warmer S(100)/S(60) ratios, cooler S(25)/S(12)ratios, and lower dust-to-H I gas mass ratios. The temperature,dust-to-H I gas mass ratios, and L(IR)/L(B) ratios do not correlate withthe metallicity of the ionized gas of the Irr's. A correlation betweenthe IR fluxes and both the H-alpha and the blue stellar fluxes is foundfor the Irr's.
| Properties of H II region populations in galaxies. I - The first-ranked H II regions
H-alpha photometry of the brightest H II regions in 95 nearby spiral andirregular galaxies has been analyzed in order to study the dependence ofthe H II region populations on the properties of their parent galaxies.It is found that the brightest H II regions in Magellanic irregulargalaxies are about 50 times brighter than those in early-type spirals ofthe same absolute magnitude. It is suggested that this difference is dueto both an increase in the numbers of H II regions in late-type galaxiesand a physical change in the characteristic sizes of the star-formingregions.
| Bursting dwarf galaxies - Implications for luminosity function, space density, and cosmological mass density
An attempt is made to estimate the true average space density ofgas-rich dwarf galaxies by comparing the luminosity and sizedistributions of visible dwarf irregulars with a set of simulatedobservations of a bursting population of galaxies on which selectioneffects corresponding to the real observations have been imposed. Thetrue size distribution is assumed to be a power law f(r) proportional tor exp y. A value of y = - 4.2 + or - 0.2 gives good agreement with theobserved frequency distributions of luminosity, optical radius, andangular size. The same model accounts for the observed luminosityfunction in the Virgo cluster. The implications of this result for thetrue shape of the Galaxy luminosity function and the contribution to thecosmological density are discussed.
| Uncertainties in 21 centimeter redshifts. I - Data
High-precision data on the 21-cm redshifts, profile widths, and shapesfor 625 galaxies are presented. Each galaxy is listed in across-identification and morphology table. High-resolution spectra arealso given for each galaxy. Internal redshift consistency is roughly 1km/s for galaxies for which the S/N is above 15. No systematic effectshave been found which might influence the observed redshift quantizationat 72.5 km/s or its submultiples.
| The CO contents of dwarf irregular galaxies
A search has been conducted for CO in 16 dwarf irregular galaxiesselected to span a wide range of infrared luminosity and color. CO wasdetected in six dwarf galaxies spanning the entire range in opticalcolor and IR luminosity. The dwarf galaxies extend by three orders ofmagnitude in luminosity the correlation between IR and CO luminositiesfound for spiral galaxies. For the dwarf galaxy sample alone, thosegalaxies with the least evidence for ongoing star formation have thelowest L(IR)/L(CO) ratios, while the active, blue dwarfs have thehighest values of this ratio. This is interpreted as evidence fordepleted values of this ratio. For galaxies with L(IR) between 100million and a trillion solar luminosities, the full range of L(IR)/L(CO)values at each luminosity. The ratio of L(IR)/L(CO) in II Zw 40 is thehighest of any galaxy in the present sample and is comparable to thevalues found in interacting galaxies.
| Star formation in active dwarf galaxies
Star formation and the ISM in active dwarf galaxies are studied based ondata from the IRAS Point Source Catalog. The dwarf galaxies that showevidence of recent energetic star formation are generally also strongfar-infrared emitters; thus, active current star formation is associatedwith a history of energetic star formation. A fraction of the galaxiesconsidered here have a star formation rate that is significantly greaterthan the average rate in the recent past. Available gas is beingconsumed as efficiently in the presently active dwarfs as in the MilkyWay. A primary difference between galaxies that are energeticallyforming stars and those that are not is the difference in gas mass, aswell as the efficiency of star formation. The most important process maybe the assembly of large amounts of gaseous material.
| Stellar populations and star formation in irregular galaxies
A review and intercomparison is conducted of data on variousmorphologically-chosen groups of irregular galaxies in order tounderstand the underlying physical mechanisms that differentiate thesesystems. Particular attention is given to the observational clues to thestellar content, star-formation processes, and star-formation historiesof these galaxies, with an emphasis on the uncertainties and the manyunanswered questions.
| High signal-to-noise ratio observations of H I in 243 galaxies
The 21 cm spectral-line system of the Arecibo Observatory was used tomeasure neutral hydrogen emission from 243 faint galaxies. Most lie nearthe plane of the Local Supercluster. All observations reach anunsmoothed signal-to-noise ratio of at least 7.0; the average for theset is 23. The resulting data are used to estimate H I masses, systemicvelocities, and accurate profile widths at 20 percent, 25 percent, 50percent, and 80 percent of peak intensity levels. The widths are used tocalibrate directly the bias introduced by popular data-smoothingoperation. The data include observations of 65 objects with previouslyunknown redshifts.
| Star-forming properties and histories of dwarf irregular galaxies - Down but not out
Spectroscopic and imaging data designed to study star formationprocesses in a sample of dwarf irregular (Irr) galaxies are presented.Although the low-surface brightness dwarf Irr's have much H I gas withwhich to form stars, the galaxy-wide star formation rates are low:typically about 10 to the -10th solar mass/yr/sq pc. The properties ofthe low-surface brightness dwarf Irr's are consistent with a constantstar formation rate equal to their current rate over approximately aHubble time. The typical star-forming regions in the dwarfs are onaverage smaller and less luminous than those in the giant Irr's,although the size distributions cover the same range, while similar togiant Irr's in many global parameters, the dwarfs have lower current andhistorical star formation rates per unit area. Dwarf Irr's have lowmetallicities relative to spirals, with typical nebular oxygenabundances falling between those of the LMC and SMC.
| Integrated magnitudes and mean colors of DDO dwarf galaxies in the UBV system. II - Distances, luminosities, and H I properties
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983AJ.....88..764D&db_key=AST
| Luminosity classifications of dwarf galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966AJ.....71..922V&db_key=AST
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