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The Second Byurakan Survey. General Catalogue
The Second Byurakan Survey (SBS) General Catalogue is presented. TheSBS, a continuation of the Markarian survey reaching fainter limitingmagnitudes, is the first survey which combines the search of galaxiesand QSOs. A total area of 991OS#square;degrees of the Northern sky wascovered with the use of three objective prisms in combination withSchott filters. The limited magnitude on the best plates reached B ~19.5.The General Catalogue consists of 3563 objects presented in two parts: aCatalogue of galaxies (1863 objects) and one of stellar objects (1700objects). The Catalogue of SBS AGN consists of 761 objects (155 SyG, 596QSOs, and 10 BLLac). Multi-wavelength data are presented for 1438 SBSobjects identified with X-ray, IRAS and FIRST sources.Spectrophotometric observations obtained over 26 years are available for3132 objects. Redshifts were measured for ~ 2100 extragalactic objects.Spectral classification is presented for ~ 2970 objects. The majority ofthe data is presented here for the first time. The Catalogue presentsnew large homogeneous deep representative complete samples of brightQSOs, AGNs, and faint UVX galaxies in the Northern sky. The SBS sampleis found to be complete at 70% for galaxies and ~ 85% for AGN/QSOs withB ≤ 17.5.
| 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.
| The Molecular Interstellar Medium of Dwarf Galaxies on Kiloparsec Scales: A New Survey for CO in Northern, IRAS-detected Dwarf Galaxies
We present a new survey for CO in dwarf galaxies using the ARO Kitt Peak12 m telescope. This survey consists of observations of the centralregions of 121 northern dwarfs with IRAS detections and no known COemission. We detect CO in 28 of these galaxies and marginally detectanother 16, increasing by about 50% the number of such galaxies known tohave significant CO emission. The galaxies we detect are comparable instellar and dynamical mass to the Large Magellanic Cloud, althoughsomewhat brighter in CO and fainter in the far-IR. Within dwarfs, wefind that the CO luminosity LCO is most strongly correlatedwith the K-band and the far-infrared luminosities. There are also strongcorrelations with the radio continuum (RC) and B-band luminosities andlinear diameter. Conversely, we find that far-IR dust temperature is apoor predictor of CO emission within the dwarfs alone, although a goodpredictor of normalized CO content among a larger sample of galaxies. Wesuggest that LCO and LK correlate well because thestellar component of a galaxy dominates the midplane gravitational fieldand thus sets the pressure and density of the atomic gas, which controlthe formation of H2 from H I. We compare our sample with moremassive galaxies and find that dwarfs and large galaxies obey the samerelationship between CO and the 1.4 GHz RC surface brightness. Thisrelationship is well described by a Schmidt law withΣRC~Σ1.3CO. Therefore,dwarf galaxies and large spirals exhibit the same relationship betweenmolecular gas and star formation rate (SFR). We find that this result isrobust to moderate changes in the RC-to-SFR and CO-to-H2conversion factors. Our data appear to be inconsistent with large (orderof magnitude) variations in the CO-to-H2 conversion factor inthe star-forming molecular gas.
| A Catalog of Neighboring Galaxies
We present an all-sky catalog of 451 nearby galaxies, each having anindividual distance estimate D<~10 Mpc or a radial velocityVLG<550 km s-1. The catalog contains data onbasic optical and H I properties of the galaxies, in particular, theirdiameters, absolute magnitudes, morphological types, circumnuclearregion types, optical and H I surface brightnesses, rotationalvelocities, and indicative mass-to-luminosity and H I mass-to-luminosityratios, as well as a so-called tidal index, which quantifies the galaxyenvironment. We expect the catalog completeness to be roughly 70%-80%within 8 Mpc. About 85% of the Local Volume population are dwarf (dIr,dIm, and dSph) galaxies with MB>-17.0, which contributeabout 4% to the local luminosity density, and roughly 10%-15% to thelocal H I mass density. The H I mass-to-luminosity and the H Imass-to-total (indicative) mass ratios increase systematically fromgiant galaxies toward dwarfs, reaching maximum values about 5 in solarunits for the most tiny objects. For the Local Volume disklike galaxies,their H I masses and angular momentum follow Zasov's linear relation,expected for rotating gaseous disks being near the threshold ofgravitational instability, favorable for active star formation. We foundthat the mean local luminosity density exceeds 1.7-2.0 times the globaldensity, in spite of the presence of the Tully void and the absence ofrich clusters in the Local Volume. The mean local H I density is 1.4times its ``global'' value derived from the H I Parkes Sky Survey.However, the mean local baryon densityΩb(<8Mpc)=2.3% consists of only a half of the globalbaryon density, Ωb=(4.7+/-0.6)% (Spergel et al.,published in 2003). The mean-square pairwise difference of radialvelocities is about 100 km s-1 for spatial separations within1 Mpc, increasing to ~300 km s-1 on a scale of ~3 Mpc. alsoWe calculated the integral area of the sky occupied by the neighboringgalaxies. Assuming the H I size of spiral and irregular galaxies to be2.5 times their standard optical diameter and ignoring any evolutioneffect, we obtain the expected number of the line-of-sight intersectionswith the H I galaxy images to be dn/dz~0.4, which does not contradictthe observed number of absorptions in QSO spectra.
| Cold dust and molecular gas towards the centers of Magellanic type galaxies and irregulars. I. The data
We present 1300 μm continuum emission measurements and observationsof the 12CO (1-0) and (2-1) transition towards the centers of64 Magellanic type galaxies (Sdm/Sm) and irregulars (Im/I0/Irr). Thesources are selected to have IRAS flux densities S100 μm≥1000 mJy and optical diameters mainly below 180 arcsec. We wereable to detect 12CO towards 41 and the continuum emissiontowards 28 galaxies. In addition, we obtained the corresponding data fora set of 6 complementary galaxies of different morphological type.Based on observations collected at ESO, La Silla, Chile and IRAM, PicoVeleta, Spain.The full version of Figs. \ref{spec1.fig} and \ref{spec2.fig} is onlyavailable in electronic form at http://www.edpsciences.org
| The Hα galaxy survey. I. The galaxy sample, Hα narrow-band observations and star formation parameters for 334 galaxies
We discuss the selection and observations of a large sample of nearbygalaxies, which we are using to quantify the star formation activity inthe local Universe. The sample consists of 334 galaxies across allHubble types from S0/a to Im and with recession velocities of between 0and 3000 km s-1. The basic data for each galaxy are narrowband H\alpha +[NII] and R-band imaging, from which we derive starformation rates, H\alpha +[NII] equivalent widths and surfacebrightnesses, and R-band total magnitudes. A strong correlation is foundbetween total star formation rate and Hubble type, with the strongeststar formation in isolated galaxies occurring in Sc and Sbc types. Moresurprisingly, no significant trend is found between H\alpha +[NII]equivalent width and galaxy R-band luminosity. More detailed analyses ofthe data set presented here will be described in subsequent papers.Based on observations made with the Jacobus Kapteyn Telescope operatedon the island of La Palma by the Isaac Newton Group in the SpanishObservatorio del Roque de los Muchachos of the Instituto deAstrofísica de Canarias.The full version of Table \ref{tab3} is available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/414/23 Reduced image datafor this survey can be downloaded fromhttp://www.astro.livjm.ac.uk/HaGS/
| Infrared Observations of Galaxies in the Local Universe. II. 391 Calibrated Images with Photometric and Structural Measurements
This paper presents empirical results from a deep imaging survey ofgalaxies in the local universe at the J and Ks wavelengths.Three hundred ninety-one images have been obtained and calibrated usingthe same camera and filter set with the Steward Observatory 1.6 m KuiperTelescope on Mount Bigelow and the 2.3 m Bok Telescope on Kitt Peak. Thelimiting magnitude is typically 22 mag arcsec-1 at J and 21mag arcsec-1 at Ks. The central surfacebrightness, apparent magnitudes, sizes, scale lengths, and inclinationsare tabulated from measurements made using these data. The purpose ofthis paper is to provide basic near-infrared data on a variety of galaxytypes.
| The Kinematic State of the Local Volume
The kinematics of galaxies within 10 Mpc of the Milky Way isinvestigated using published distances and radial velocities. Withrespect to the average Hubble flow (isotropic or simple anisotropic),there is no systematic relation between peculiar velocity dispersion andabsolute magnitude over a range of 10 mag; neither is there any apparentvariation with galaxy type or between field and cluster members. Thereare several possible explanations for the lack of variation, though allhave difficulties: either there is no relationship between light andmass on these scales, the peculiar velocities are not produced bygravitational interaction, or the background dynamical picture is wrongin some systematic way. The extremely cold local flow of 40-60 kms-1 dispersion reported by some authors is shown to be anartifact of sparse data, a velocity dispersion of over 100 kms-1 being closer to the actual value. Galaxies with a high(positive) radial velocity have been selected against in studies of thisvolume, biasing numerical results.
| Spectroscopic Study of a Large Sample of Galaxies Discovered in the Second Byurakan Survey Fields
The Second Byurakan Survey (SBS) is a well known combined survey, whichuses the presence of UV-excess radiation in the continuum, or thepresence of emission-lines in the spectra for the identification ofactive and star-forming galaxies. This paper reports on a comparativestudy of 77 galaxies identified with UV-excess, and 34 galaxiesidentified via emission-line techniques in the fields of the SBS. Thespectroscopic parameters used for the comparison are the [OII]3727/H and[OIII]5007/H emission-lines ratios, the equivalent widths of [OII]3727,[OIII]5007 and H emission-lines, and the C [OII]-C H index.Spectroscopic parameters as well as new redshifts were determined fromthe spectra obtained with the 6m telescope of the Special AstrophysicalObservatory (Russia). The main results are: 1) Galaxies discovered viaUV-excess technique are preferably more active. 2) Galaxies discoveredvia emission-line technique are preferably high-excitationlow-luminosity star-forming galaxies. 3) UV-excess galaxies withfaintest UV-excess radiation are likely candidates to be LINER or Sy2type objects.
| Distribution of star-forming complexes in dwarf irregular galaxies
We study the distribution of bright star-forming complexes in ahomogeneous sample of 72 late-type (``irregular'') dwarf galaxieslocated within the 10 Mpc volume. Star-forming complexes are identifiedas bright lumps in B-band galaxy images and isolated by means of theunsharp-masking method. For the sample as a whole the radial numberdistribution of bright lumps largely traces the underlyingexponential-disk light profiles, but peaks at a 10 percent smaller scalelength. Moreover, the presence of a tail of star forming regions out toat least six optical scale lengths provides evidence against asystematic star formation truncation within that galaxy extension.Considering these findings, we apply a scale length-independentconcentration index, taking into account the implied non-uniform randomspread of star formation regions throughout the disk. The numberprofiles frequently manifest a second, minor peak at about two scalelengths. Relying on a two-dimensional stochastic self-propagating starformation model, we show these secondary peaks to be consistent withtriggered star formation; for a few of the brighter galaxies a peculiarpeak distribution is observed that is conceivably due to the onset ofshear provided by differential rotation. On scales between 100 and 1000pc, and by taking into account exponential-disk structure, bright lumpsreveal cluster dimensions between 1.3 and 2, with a weak trend to higherdimensions for brighter galaxies. Cluster dimension weaklyanticorrelates with the lumpiness index (the fraction of the totalgalaxy light due to the light contributed by the lumps), the latterindex showing no dependence on luminosity. Lump spreading within thedisk, as measured by the concentration index, and lump clustering, asgiven by the cluster dimension, are not linked to each other.Interpreting cluster dimension in terms of porosity of a self-similarintragalactic medium, we derive a relation between current starformation rate, scale length, and porosity.
| Local galaxy flows within 5 Mpc
We present Hubble Space Telescope/WFPC2 images of sixteen dwarf galaxiesas part of our snapshot survey of nearby galaxy candidates. We derivetheir distances from the luminosity of the tip of the red giant branchstars with a typical accuracy of ~ 12%. The resulting distances are4.26 Mpc (KKH 5), 4.74 Mpc (KK 16), 4.72 Mpc (KK 17), 4.66 Mpc (ESO115-021), 4.43 Mpc (KKH 18), 3.98 Mpc (KK 27), 4.61 Mpc (KKH 34), 4.99Mpc (KK 54), 4.23 Mpc (ESO 490-017), 4.90 Mpc (FG 202), 5.22 Mpc (UGC3755), 5.18 Mpc (UGC 3974), 4.51 Mpc (KK 65), 5.49 Mpc (UGC 4115), 3.78Mpc (NGC 2915), and 5.27 Mpc (NGC 6503). Based on distances and radialvelocities of 156 nearby galaxies, we plot the local velocity-distancerelation, which has a slope of H0 = 73 km s-1Mpc-1 and a radial velocity dispersion of 85 kms-1. When members of the M81 and Cen A groups are removed,and distance errors are taken into account, the radial velocitydispersion drops to sigmav = 41 km s-1. The localHubble flow within 5 Mpc exhibits a significant anisotropy, with twoinfall peculiar velocity regions directed towards the Supergalacticpoles. However, two observed regions of outflow peculiar velocity,situated on the Supergalactic equator, are far away ( ~ 50degr ) fromthe Virgo/anti-Virgo direction, which disagrees with a sphericallysymmetric Virgo-centric flow. About 63% of galaxies within 5 Mpc belongto known compact and loose groups. Apart from them, we found six newprobable groups, consisting entirely of dwarf galaxies.Based on observations made with the NASA/ESA Hubble Space Telescope. TheSpace Telescope Science Institute is operated by the Association ofUniversities for Research in Astronomy, Inc. under NASA contract NAS5-26555.}\fnmsep\thanks{Table 2, and Figs. 1 and 2, are only availablein electronic form at http://www.edpsciences.org
| Galaxy flow in the Canes Venatici I cloud
We present an analysis of Hubble Space Telescope/WFPC2 images ofeighteen galaxies in the Canes Venatici I cloud. We derive theirdistances from the luminosity of the tip of the red giant branch starswith a typical accuracy of ~ 12%. The resulting distances are 3.9 Mpc(UGC 6541), 4.9 Mpc (NGC 3738), 3.0 Mpc (NGC 3741), 4.5 Mpc (KK 109),>6.3 Mpc (NGC 4150), 4.2 Mpc (UGC 7298), 4.5 Mpc (NGC 4244), 4.6 Mpc(NGC 4395), 4.9 Mpc (UGC 7559), 4.2 Mpc (NGC 4449), 4.4 Mpc (UGC 7605),4.6 Mpc (IC 3687), 4.7 Mpc (KK 166), 4.7 Mpc (NGC 4736), 4.2 Mpc (UGC8308), 4.3 Mpc (UGC 8320), 4.6 Mpc (NGC 5204), and 3.2 Mpc (UGC 8833).The CVn I cloud has a mean radial velocity of 286 +/- 9 kms-1, a mean distance of 4.1 +/- 0.2 Mpc, a radial velocitydispersion of 50 km s-1, a mean projected radius of 760 kpc,and a total blue luminosity of 2.2 x 1010 Lsun .Assuming virial or closed orbital motions for the galaxies, we estimatedtheir virial and their orbital mass-to-luminosity ratio to be 176 and 88Msun /Lsun , respectively. However, the CVn Icloud is characterized by a crossing time of 15 Gyr, and is thus farfrom a state of dynamical equilibrium. The large crossing time for thecloud, its low content of dSph galaxies (<6%), and the almost``primordial'' shape of its luminosity function show that the CVn Icomplex is in a transient dynamical state, driven rather by the freeHubble expansion than by galaxy interactions.Based on observations made with the NASA/ESA Hubble Space Telescope. TheSpace Telescope Science Institute is operated by the Association ofUniversities for Research in Astronomy, Inc. under NASA contract NAS5-26555.Figures 1 and 2 are only available in electronic form athttp://www.edpsciences.org
| The Westerbork HI survey of spiral and irregular galaxies. II. R-band surface photometry of late-type dwarf galaxies
R-band surface photometry is presented for 171 late-type dwarf andirregular galaxies. For a subsample of 46 galaxies B-band photometry ispresented as well. We present surface brightness profiles as well asisophotal and photometric parameters including magnitudes, diameters andcentral surface brightnesses. Absolute photometry is accurate to 0.1 magor better for 77% of the sample. For over 85% of the galaxies the radialsurface brightness profiles are consistent with published data withinthe measured photometric uncertainty. For most of the galaxies in thesample H I data have been obtained with the Westerbork Synthesis RadioTelescope. The galaxies in our sample are part of the WHISP project(Westerbork H I Survey of Spiral and Irregular Galaxies), which aims atmapping about 500 nearby spiral and irregular galaxies in H I. Theavailability of H I data makes this data set useful for a wide range ofstudies of the structure, dark matter content and kinematics oflate-type dwarf galaxies. Based on observations made with INT operatedon the island of La Palma by the Isaac Newton Group in the SpanishObservatorio del Roque de los Muchachos of the Instituto de Astrofisicade Canarias. The tables in Appendix A are only available in electronicform at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/390/863. Thefigures in Appendix B are only available in electronic formhttp://www.edpsciences.org
| Structure and stellar content of dwarf galaxies. VII. B and R photometry of 25 southern field dwarfs and a disk parameter analysis of the complete sample of nearby irregulars
We present B and R band surface photometry of 25 Southern field dwarfgalaxies within a distance of 10 Mpc. For each galaxy we give theessential model-free photometric parameters and, by fitting exponentialsto the surface brightness profiles, the central extrapolated surfacebrightness and the exponential scale length, in both colour bands.Surface brightness and colour profiles are shown. One of the objects, avery faint dwarf elliptical in the vicinity of NGC 2784, has beendiscovered in the course of this work. Drawing on the data from this andall previous papers of this series, we construct a complete sample of 72late-type (``irregular'') dwarf galaxies in nearby groups and the fieldwithin the 10 Mpc volume, to study the exponential-disk parameterrelations of these galaxies with respect to galaxy environment. Weconfirm our previous finding of statistically lower scale lengths/highercentral surface brightnesses for field and group galaxies as compared tocluster galaxies. However, using a clear-cut definition of ``group''versus ``field'' environment, we find no significant difference in thephotometric structure of group and field irregulars. A difference in thestar formation history may partly account for this structure-environmentrelation: for a given luminosity cluster dwarfs are on average redderthan field and group galaxies. We also report evidence for the colourgradients of dwarf irregulars being roughly inversely proportional tothe disk scale lengths. Supplementing our photometric data withkinematic data from the literature, we study possible relations withkinematic properties of the inner disk. Applying the dark matter scalingrelations for a Burkert halo we show that for field and group galaxiesof a given luminosity faster-than-mean disk rotational velocities at aradius of about two scale lengths are correlated with larger-than-meandisk scale lengths. Based on observations collected at the EuropeanSouthern Observatory, La Silla, Chile. Table 3 containing ``BRphotometry and kinematic data for the 72 irregular dwarf galaxies of ourcomplete sample'' is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/388/29
| The Morphologies of Dwarf Markarian Galaxies
The morphologies of the 96 dwarf (M(B) -17m) galaxies in the Markariancatalog are determined from the digitized Schmidt plates obtained forthe construction of the Hubble Space Telescope Guide Star Catalog. Thefraction of double nucleus galaxies within the dwarf Markarian galaxiesis determined to be twice that found for all galaxies in the Markariancatalog. In addition to the 12 previously known cases, four definite andtwo probable galaxies with double nuclei are identified. The fraction ofdwarf Markarian galaxies with bright star forming regions is found to betwice that of Virgo cluster dwarf galaxies. No Elliptical galaxies arefound in the sample. Galaxies with blue compact dwarf and S0morphologies are more often found to contain unresolved regions of UVexcess emission. Dwarf Markarian galaxies with different morphologicalstructures and spectral classes are found to have similar FIRproperties.
| Multiwavelength study of the nuclei of a volume-limited sample of galaxies - I. X-ray observations
We discuss ROSAT HRI X-ray observations of 33 very nearby galaxies,sensitive to X-ray sources down to a luminosity of approximately1038ergs-1. The galaxies are selected from acomplete, volume-limited sample of 46 galaxies with LX ∝L1.5host d < 7 MPc for which we have extensivemultiwavelength data. For an almost complete subsample withMB < -14 MB (29/31 objects) we have HRI images.Contour maps and source lists are presented within the central region ofeach galaxy, together with nuclear upper limits where no nuclear sourcewas detected. Nuclear X-ray sources are found to be very common,occurring in ~35per cent of the sample. Nuclear X-ray luminosity isstatistically connected to host galaxy luminosity - there is not a tightcorrelation, but the probability of a nuclear source being detectedincreases strongly with galaxy luminosity, and the distribution ofnuclear luminosities seems to show an upper envelope that is roughlyproportional to galaxy luminosity. While these sources do seem to be agenuinely nuclear phenomenon rather than nuclear examples of the generalX-ray source population, it is far from obvious that they are miniatureSeyfert nuclei. The more luminous nuclei are very often spatiallyextended, and Hii region nuclei are detected just as often as LINERs.Finally, we also note the presence of fairly common superluminous X-raysources in the off-nuclear population - out of 29 galaxies we find ninesources with a luminosity greater than 1039ergs-1.These show no particular preference for more luminous galaxies. One isalready known to be a multiple SNR system, but most have no obviousoptical counterpart and their nature remains a mystery.
| 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.
| Accurate optical positions for 2978 objects from the Second Byurakan Survey (SBS) with the Digitized Sky Survey
Optical positions of 2978 objects listed in the Second Byurakan Survey(SBS) were obtained using the Digitized Sky Survey (DSS), and are givenwith an rms uncertainty ~ 1 arcsec in each coordinate. Tables 1 and 2are only available in electronic form at the CDS via anonymous ftp130.79.128.5 or via http://cdsweb.u-strasbg.fr/Abstract.html
| Galaxy Interactions in the Local Volume
We consider a sample of 240 galaxies with V0 < 500 km/s.At the present its completness is expected to be about 60%. Being almostdistance limited, the sample ( = Local Volume = VL) has the mean numberdensity ~0.25 gal/Mpc3. According to Vorontsov-Velyaminov andArp a fraction of interacting galaxies in the LV consists of 7%, butdrops to 2% when confusions with isolated irregular galaxies are takeninto account. A relative number of apparent mergers in the LV sampleseems to be ~3%. We use a quantitative approach, where each of the LVgalaxies has a "tidal index" TI = MAX Mi /Ri3, i = 1,... N expressed via masses andseparations of the galaxy neighbours. We present a total list of the LVgalaxies with their "Main Disturbers" ( = MD) and give properties of theLV sample: * Being ranked according to their MDs the LV galaxies form"nests" with a population "k" from 1 to 22 members. The quantity "k"plotted against the MD mass shows a relation: k propto M1/2.* The whole sample contains 64 MDs, but only 7 the most massive of themcontrol 51% of the LV population. * There is no clear evidence for masssegregation on a scale of [0.3 -- 3] Mpc. * Almost all of the galaxieshaving high TI lie within 0.5 Mpc respect to the Supergalactic plane,while isolated objects are distributed over the whole LV. * About 35% ofthe galaxies have so low TI, their crossing time with respect to theirMDs exceeds the cosmological time, 1/H.
| 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.
| HI properties of nearby galaxies from a volume-limited sample
We consider global HI and optical properties of about three hundrednearby galaxies with V_0 < 500 km s(-1) . The majority of them haveindividual photometric distance estimates. The galaxy sample parametersshow some known and some new correlations implying a meaningful dynamicexplanation: 1) In the whole range of diameters, 1 - 40 Kpc, the galaxystandard diameter and rotational velocity follows a nearly linearTully-Fisher relation, lg A25~(0.99+/-0.06)lg V_m. 2) The HImass-to-luminosity ratio and the HI mass-to-``total" mass (inside thestandard optical diameter) ratio increase systematically from giantgalaxies towards dwarfs, reaching maximum values 5 ;M_ȯ/L_ȯand 3, respectively. 3) For all the Local Volume galaxies their totalmass-to-luminosity ratio lies within a range of [0.2-16]M_ȯ/L_ȯ with a median of 3.0 ;M_ȯ/L_ȯ. TheM25/L ratio decreases slightly from giant towards dwarfgalaxies. 4) The M_HI/L and M25/L ratios for the samplegalaxies correlate with their mean optical surface brightness, which maybe caused by star formation activity in the galaxies. 5) The M_HI/L andM25/L ratios are practically independent of the local massdensity of surrounding galaxies within the range of densities of aboutsix orders of magnitude. 6) For the LV galaxies their HI mass andangular momentum follow a nearly linear relation: lgM_HI~(0.99+/-0.04)lg (V_m* A25), expected for rotatinggaseous disks being near the threshold of gravitational instability,favourable for active star formation. Table in the Appendix is availableonly in electronic form at the CDS via anonymous ftp 130.79.128.5 orhttp//cdsweb.u-strasbg.fr/Abstract.html
| HI observations of blue compact galaxies from the first and second Byurakan surveys
We present the results of a neutral hydrogen survey of 79 galaxies froma statistical sample of 88 Blue Compact Galaxies (BCGs) selected fromthe First and Second Byurakan objective prism surveys to have a HIIregion-like spectrum, an equivalent width of the [O III] lambda 5007line larger than ~ 50 Å, and a velocity <= 6000 km s(-1) . Thedetection rate for the statistical sample is 74%. HI masses rangebetween 4 10(7)M_sun) and 5 10(9) M_sun with the HI mass distributionpeaking at 3 10(8) M_sun. The full width at half-maximum of the HIprofile varies between ~ 30 km s(-1) and 160 km s(-1) , with a mean of ~92 km s(-1) . These small widths are characteristic of dwarf galaxies.For comparison, we have also observed an additional 92 BCGs with weakerstar formation and/or larger distances, and/or interesting astrophysicalproperties. These in general have larger widths and HI masses.Tables~1,~2,~3 also available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Structure and stellar content of dwarf galaxies. III. B and R photometry of dwarf galaxies in the M 101 group and the nearby field
We have carried out CCD photometry in the Cousins B and R bands of 21dwarf galaxies in and around the M 101 group. Elevenare members and suspected members of the group and ten are fieldgalaxies in the projected vicinity of the group. We have derived totalmagnitudes, effective radii, effective surface brightnesses, as well asgalaxy diameters at various isophotal levels in both colours.Best-fitting exponential parameters and colour gradients are also givenfor these galaxies. Some of the galaxies show a pronounced luminosityexcess above the best-fitting exponential at large radii, or surfacebrightnesses fainter than ~ 26 mag/sq arcsec in R. This feature, whilenon-significant for a single case and technically difficult tointerpret, might be an indication of the existence of an extended oldstellar halo in dwarf irregulars. The photometric parameters of thegalaxies presented here will be combined with previously published datafor nearby dwarf galaxies and statistically analysed in a forthcomingpaper. Based on observations made at Observatoire de Haute Provence(CNRS), France.}
| Infrared Observations of Galaxies in the Local Universe. I. The Survey and Some Representative Results
This paper introduces a continuing survey of galaxies in the localuniverse. Consistent deep images are being acquired for a representativesample of 321 galaxies in the Uppsala General Catalogue down to 21.7 magarcsec-2 at Ks (2.16 mu m) and 22.4 mag arcsec-2 at J (1.25 mu m) usinga NICMOS camera with a 3.'8 x 3.'8 field of view attached to the 61 inch(1.5 m) telescope on Mount Bigelow. We provide some examples of theresults being obtained by employing 64 deep images of a subset of 44galaxies. Bulge-to-disk ratios are tabulated for 30 galaxies. Thebrightness of the central region of 44 galaxies declines approximately 5mag from Hubble type S0 to Sm. An exponential vertical scale height atKs is found to be 500 pc for the disk of UGC 5173. Arm amplitudes offour nearly face-on spiral galaxies are found to range between 11% and88% compared to the interarm region. There is some evidence that the armamplitude is larger at Ks than it is at J. Color gradients are measuredfor 15 galaxies with only one showing a significant nonzero result. Ameasurement of galactic symmetry applied to 64 deep images reveals anaverage asymmetry of 7.6% ( sigma = 4.6%) for these galaxies.
| Groups of galaxies. III. Some empirical characteristics.
Not Available
| CCD imaging of twenty nearby isolated irregular galaxies
We present B, V and I CCD stellar photometry for a sample of 20 fieldirregular dwarf galaxies. Their corrected radial velocity is V_0 <500 km s(-1) . Most of them have been resolved into stars for the firsttime. Based on photometry of their brightest blue stars we have derivedthe following distances: 5.9 Mpc (UGC 685), 5.4 Mpc (UGC 1281), 7.2 Mpc(UGC 3303), 7.0 Mpc (UGC 3476), 7.3: Mpc (UGC 3600), 7.2: Mpc (UGC3698), 7.9 Mpc (NGC 2337), 8.6 Mpc (UGC 3817), 5.7 Mpc (UGC 3860), 5.6Mpc (UGC 4426), >=7.9 Mpc (F 565-v1), 7.4: Mpc (UGC 5086), 7.1 Mpc(UGC 5272), 5.9 Mpc (UGC 5340), 7.1 Mpc (UGC 5427), 2.7: Mpc (UGC 5456),6.6 Mpc (NGC 3274), 9.3 Mpc (UGC 5889), 5.2 Mpc (NGC 5238), and 8.0 Mpc(UGC 9405). Our sample exhibits diverse morphological propertiesevidently caused by their different starburst activity. The galaxysample has a median integral absolute magnitude M_B = -14.6 and a medianintegral colour (B-V)_T = +0.47. One dwarf, UGC 5340, stands out by itsvery blue colour, (B-V)_T = +0.18, and by its high M(HI)/L ratio, asexpected for young galaxies. Four objects of the sample are IRASsources. Being well isolated systems, the considered galaxies may beused to estimate a local value of the Hubble parameter, H = V_0/D. Forhalf of the sample galaxies their individual H- values are concentratedwithin [58-68] km s(-1) /Mpc with a median of 65 km s(-1) /Mpc. Tables2--17 are only available in electronic form at the CDS via anonymous ftpto cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Detailed images and distance measurements for eighteen dwarf irregular galaxies in the Canes Venatici cloud
In the Canes Venatici cloud, eighteen dwarf irregular galaxies wereobserved in B, V bands at the Nordic Optical Telescope under a seeing ofone arcsec. Most of the galaxies having radial velocities V_0 < 500km/s have been resolved into stars for the first time. The galaxydistances were derived based on photometry of their brightest bluestars. Distances to some of the galaxies: UGC 6782, UGC 7131 and,probably, K 215, which are located at the CVn southern edge, wereestimated to be about 15 Mpc, which is typical of the Virgo clusteroutskirts. For two LSB galaxies, K 200 and K 215, the distances may beoverestimated, probably because of a lack of young massive stars. Forthe remaining galaxies: UGC 7559, UGC 7599, UGC 7605, UGC 7639, UGC7698, UGCA 290, UGCA 292, UGC 7866, UGC 8024, UGC 8638, UGC 8651, UGC8760, and UGC 8833 the estimated distances range from 2.3 to 8.0 Mpc,indicating their actual membership in the CVn cloud. Several objectsstudied here (UGC 7605, UGC 7639, UGC 8638, UGC 8833) have awell-resolved bluish core and regular yellow outer parts, which maypoint to composite (new and old) populations. The galaxy UGCA 292 = CVndwA has unusual global parameters: (B-V)_T=+0.08, M_T=-11.4, M(HI)/L_B =6\ M_sun/L_sun and M(HI)/M_T =0.7, being, perhaps, one of the youngestknown objects in the Local Universe. Table 2 to 19 are only available atthe CDS via anonymous ftp 130.79.128.5 or viahttp://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.
| A catalogue of spatially resolved kinematics of galaxies: Bibliography
We present a catalogue of galaxies for which spatially resolved data ontheir internal kinematics have been published; there is no a priorirestriction regarding their morphological type. The catalogue lists thereferences to the articles where the data are published, as well as acoded description of these data: observed emission or absorption lines,velocity or velocity dispersion, radial profile or 2D field, positionangle. Tables 1, 2, and 3 are proposed in electronic form only, and areavailable from the CDS, via anonymous ftp to cdsarc.u-strasbg.fr (to130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| Nearby galaxies. IV. The global Hubble parameter and the dispersion of the Hubble relation
Using a spherically symmetric model of the Virgo flow the global Hubbleparameter has been estimated from the observed radial velocities and thephotometrically measured distances of nearby galaxies. Adopting theobserved recession velocity of the Virgo Cluster to about 1000 km s(-1)and the infall velocity of the Local Group to 350 km s(-1) the globalHubble constant results to 73 +/- 10 km s(-1) Mpc(-) -1. This valuecorresponds with the distance of the Virgo Cluster of 18 +/- 2 Mpc. Thecosmic dispersion of the galaxies around the Hubble relation is of orderof 35 km s(-1) .
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