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|UBR charge-coupled device photometry of Stromlo-APM galaxies|
We present charge-coupled device (CCD) photometry in theJohnson-Kron-Cousins UBR bands for a sample of 320 galaxies selectedfrom the Stromlo-APM Redshift Survey. We use these CCD data to estimatethe galaxy luminosity function in the U, B, R and bJ bands,finding consistent results with earlier work. Fainter galaxiesserendipitously observed on our CCD frames allow a check of thephotometric calibration of the APM Galaxy Survey. We find no evidence ofany significant scale error in the APM magnitudes.
|Galaxy interactions - poor starburst triggers. III. A study of a complete sample of interacting galaxies|
We report on a study of tidally triggered star formation in galaxiesbased on spectroscopic/photometric observations in the optical/near-IRof a magnitude limited sample of 59 systems of interacting and merginggalaxies and a comparison sample of 38 normal isolated galaxies. From astatistical point of view the sample gives us a unique opportunity totrace the effects of tidally induced star formation. In contrast toresults from previous investigations, our global UBV colours do notsupport a significant enhancement of starforming activity in theinteracting/merging galaxies. We also show that, contrary to previousclaims, there is no significantly increased scatter in the colours ofArp galaxies as compared to normal galaxies. We do find support formoderate (a factor of ~ 2-3) increase in star formation in the verycentres of the interacting galaxies of our sample, contributingmarginally to the total luminosity. The interacting and in particularthe merging galaxies are characterized by increased far infrared(hereafter FIR) luminosities and temperatures that weakly correlate withthe central activity. The LFIR/LB ratio however,is remarkably similar in the two samples, indicating that truestarbursts normally are not hiding in the central regions of the FIRluminous cases. The gas mass-to-luminosity ratio in optical-IR ispractically independent of luminosity, lending further support to thepaucity of true massive starburst galaxies triggered byinteractions/mergers. We estimate the frequency of such cases to be ofthe order of ~ 0.1% of the galaxies in an apparent magnitude limitedsample. Our conclusion is that interacting and merging galaxies, fromthe global star formation aspect, generally do not differ dramaticallyfrom scaled up versions of normal, isolated galaxies. No drastic changewith redshift is expected. One consequence is that galaxy formationprobably continued over a long period of time and did not peak at aspecific redshift. The effects of massive starbursts, like blowoutscaused by superwinds and cosmic reionization caused by starburstpopulations would also be less important than what is normally assumed.Based on observations collected at the European Southern Observatory, LaSilla, Chile.
|A New Look at the Holes of IC 2574|
Several scenarios have been proposed to explain the existence of H Iholes in galaxies. In this work, the properties of the holes and shellsin the nearby dwarf galaxy IC 2574 are used to test the differentmodels. We report that the distribution of the kinematic ages of theholes located at the receding side of the galaxy is remarkably differentfrom the distribution for the holes situated at the approaching side.The mean values of the kinematic ages are 16.45+/-5.0 Myr and30.0+/-13.0[10.5] Myr, respectively. We estimate a probability of lessthan 4×10-3 that the age distributions were drawn atrandom. An asymmetry between both sides is also found in the photometricproperties and in the H I mass. These results are interpreted asevidence in favor of a connection between the star formation activityand the formation of holes in the interstellar medium, in accordancewith the predictions of the classical hypothesis that shells are createdby multiple supernova explosions. In addition, we find that thealternative scenarios face substantial difficulties and, so far, none ofthem can convincingly explain the observed abundance of sphericallyexpanding shells. After an examination of the different alternativemodels, we conclude that most of the holes in IC 2574 are likely theresult of multiple supernova explosions.
|High-resolution radio observations of Seyfert galaxies in the extended 12-μm sample - II. The properties of compact radio components|
We discuss the properties of compact nuclear radio components in Seyfertgalaxies from the extended 12-μm AGN sample of Rush et al. Our mainresults can be summarized as follows. Type 1 and type 2 Seyferts producecompact radio components which are indistinguishable in strength andaspect, indicating that their central engines are alike, as proposed bythe unification model. Infrared IRAS fluxes are more closely correlatedwith low-resolution radio fluxes than high-resolution radio fluxes,suggesting that they are dominated by kiloparsec-scale, extranuclearemission regions; extranuclear emission may be stronger in type 2Seyferts. Early-type Seyfert galaxies tend to have stronger nuclearradio emission than late-type Seyfert galaxies. V-shaped extendedemission-line regions, indicative of `ionization cones', are usuallyfound in sources with large, collimated radio outflows. Hidden broadlines are most likely to be found in sources with powerful nuclear radiosources. Type 1 and type 2 Seyferts selected by their IRAS 12-μm fluxdensities have well-matched properties.
|Star Formation in the Interacting Pair NGC 7733/7734|
The problem of star formation within the interacting pair NGC 7733/34has been studied based on the UBVRI photometry of the source. Thedistribution of the colors of selected regions within the galaxies isused to infer an estimate for the age distribution of the star-formingregions. The results seem to indicate the presence of numerous extendedyoung star-forming regions in the disk of one of the two galaxies, NGC7733, with ages in the range 106-108 yr. However,there exists no evidence for any violent star formation activity in thepast 108 yr in the nuclei of the two galaxies. The pair seemsto be a merger-bound system with the brightest and youngest site ofstar-forming activity lying at the disk interface.
|The K-band luminosity function of nearby field galaxies|
We present a measurement of the K-band luminosity function (LF) of fieldgalaxies obtained from near-infrared imaging of a sample of 345 galaxiesselected from the Stromlo-APM Redshift Survey. The LF is reasonably wellfitted over the 10-mag range -26<=MK<=-16 by aSchechter function with parameters α=-1.16+/-0.19,M*=-23.58+/-0.42 and φ*=0.012+/-0.008Mpc-3, assuming aHubble constant of H0=100kms-1Mpc-1. Wehave also estimated the LF for two subsets of galaxies subdivided by theequivalent width of the Hα emission line atEW(Hα)=10Å. There is no significant difference in LF shapebetween the two samples, although there is a hint (~1σsignificance) that emission-line galaxies (ELGs) have M* roughly 1magfainter than non-ELGs. Contrary to the optical LF, there is nodifference in faint-end slope α between the two samples.
|Surface photometry of binary galaxies.|
|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.
|CO and HI in a southern sample of interacting galaxies. I. The data|
Using SEST, the Parkes antenna and the Australia Telescope CompactArray, we have made a survey of the ^12CO(1-0) and HI emission of anoptically-selected sample of ~60 southern interacting and merginggalaxies. In this paper we present the data and determine global massesof neutral gas (in molecular and atomic form) for the observed galaxies.We have detected HI in 26 systems and found that these galaxies haveless than 15% of their gas in molecular form. Figure 3 in its entirelyis only available in electronic form at CDS via anonymous ftp tocdsarc.u-strasbg.fr (184.108.40.206) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
|The Stromlo-APM Redshift Survey. IV. The Redshift Catalog|
The Stromlo-APM Redshift Survey consists of 1797 galaxies with b_J_ <17.15 selected randomly at a rate of 1 in 20 from automated platemeasurement (APM) scans. The survey covers a solid angle of 1.3 sr (4300deg^2^) in the south Galactic cap. Redshifts have been measured for 1790(99.6%) of the galaxies. The median galaxy recession velocity is 15,300km s^-1^, and so the volume probed is V ~ 1.38 x 10^6^ h^-3^ Mpc^3^. Inthis paper we describe the construction of the redshift catalog andpresent the survey data.
|Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation|
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
|Candidates for a southern extension of the Karachentsev catalogue of isolated pairs of galaxies.|
|The Catalog of Southern Ringed Galaxies|
The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensivecompilation of diameters, axis ratios, relative bar position angles, andmorphologies of inner and outer rings, pseudorings, and lenses in 3692galaxies south of declination -17 deg. The purpose of the catalog is toevaluate the idea that these ring phenomena are related to orbitalresonances with a bar or oval in galaxy potentials. The catalog is basedon visual inspection of most of the 606 fields of the Science ResearchCouncil (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, andPalomar Sky surveys used as auxiliaries when needed for overexposed coreregions. The catalog is most complete for SRC fields 1-303 (mostly southof declination -42 deg). In addition to ringed galaxies, a list of 859mostly nonringed galaxies intended for comparison with other catalogs isprovided. Other findings from the CSRG that are not based on statisticsare the identification of intrinsic bar/ring misalignment; bars whichunderfill inner rings; dimpling of R'1pseudorings; pointy, rectangular, or hexagonal inner or outer ringshapes; a peculiar polar-ring-related system; and other extreme examplesof spiral structure and ring morphology.
|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.
|A study of a complete sample of interacting galaxies. II. Images, colour distributions and spectra.|
We present broadband images, two-colour maps and spectra of a magnitudelimited sample of interacting and merging galaxies.
|The extended 12 micron galaxy sample|
We have selected an all-sky (absolute value of b greater than or equalto 25 deg) 12 micron flux-limited sample of 893 galaxies from the IRASFaint Source Catalog, Version 2 (FSC-2). We have obtained accurate totalfluxes in the IRAS wavebands by using the ADDSCAN procedure for allobjects with FSC-2 12 micron fluxes greater than 0.15 Jy and increasingflux densities from 12 to 60 microns, and defined the sample by imposinga survey limit of 0.22 Jy on the total 12 micron flux. Its completenessis verified, by means of the classical log N - log S andV/Vmax tests, down to 0.30 Jy, below which we have measuredthe incompleteness down to the survey limit, using the log N - log Splot, for our statistical analysis. We have obtained redshifts (mostlyfrom catalogs) for virtually all (98.4%) the galaxies in the sample.Using existing catalogs of active galaxies, we defined a subsample of118 objects consisting of 53 Seyfert 1s and quasars, 63 Seyfert 2s, andtwo blazars (approximately 13% of the full sample), which is the largestunbiased sample of Seyfert galaxies ever assembled. Since the 12 micronflux has been shown to be about one-fifth of the bolometric flux forSeyfert galaxies and quasars, the subsample of Seyferts (includingquasars and blazars) is complete not only to 0.30 Jy at 12 microns butalso with respect to a bolometric flux limit of approximately 2.0 x10-10 ergs/s/sq cm. The average value of V/Vmaxfor the full sample, corrected for incompleteness at low fluxes, is 0.51+/- 0.04, expected for a complete sample of uniformly distributedgalaxies, while the value for the Seyfert galaxy subsample is 0.46 +/-0.10. We have derived 12 microns and far-infrared luminosity functionsfor the AGNs, as well as for the entire sample. We extracted from oursample a complete subsample of 235 galaxies flux-limited (8.3 Jy) at 60microns. The 60 micron luminosity function computed for this subsampleis in satisfactory agreement with the ones derived from the brightgalaxy sample (BGS) and the deep high-galactic latitude sample, bothselected at 60 microns.
|The plane W(Na I) X W(Mg I) - Effects of interstellar Na I in a sample of southern galaxies|
Galaxy spectra from a subsample of the Southern Sky Redshift Survey databank were used to study the equivalent width plane for the lines Na Ilambda 5893 A vs Mg I lambda 5175 A. An estimate of how important thecontribution of the interstellar gas for the sodium line is compared tothat of the stellar population. The sample is made up of galaxies withmorphological types from E to Sc and are distributed up to radialvelocities of 25,000 km/s, most of them smaller than 15,000 km/s. Mostearly type galaxies with dust lanes, particularly nearly edge-on So's,present an enhancement of the Na I line. Inclined spiral galaxies tendto present enhanced Na I with respect to face-on spirals. This tendency,previously found in a smaller sample of galaxies limited to V equal toor less than 6000 km/s, is now confirmed for more distant ones. In thelarge velocity sample it shows the global bulge rather than the verynucleus; the persistence of the effect suggests that the scale height ofthe gas layer in the central disk can reach a considerable fraction ofthe bulge radius.
|A study of a complete sample of interacting galaxies. I - Presentation of the sample and the UBVRIJHK photometry|
An investigation is presented on what effects galaxy-galaxy interactionhas on the properties of the involved galaxies. A magnitude limitedsample of interacting galaxies is presented, together with a controlsample of isolated galaxies. The Cousins UBVRI and Johnson JHKphotometry of all galaxies included in the samples is also presented.
|A catalogue of Seyfert galaxies.|
|The enhancement of infrared emission in interacting galaxies|
Selected infrared properties, based on IRAS observations, of twocategories of interacting galaxy pairs from the Arp-Madore Catalogue ofSouthern Peculiar Galaxies and Associations are examined. For pairs ofcomparably sized galaxies, a strong tendency exists for pairs with thehighest far-IR color temperatures to have the smallest separation. Thisfinding implies that galaxy interactions significantly enhance theintensity or the efficiency of star formation. No trend of far-IR colortemperature varying with pair separation is found for pairs consistingof a galaxy with a small companion. There are 10 times as many pairs inthe sample that contain one IRAS far-IR galaxy as there are pairs forwhich both galaxies were detected by IRAS, thus strengthening previousconclusions that the effect of a perturbation depends strongly on thedetailed geometry of the interaction.
|New southern galaxies with active nuclei|
A list of AGN candidates, identified from optical spectra taken as partof an ongoing redshift survey of southern galaxies, is presented. Theidentification, coordinates, morphological type, measured heliocentricradial velocity, and proposed emission type are given for the galaxiesshowing evidence of nonstellar nuclear activity. Using standarddiagnostics, several new Seyferts and low-ionization nuclear-emissionregions (LINERs) are identified among the emission-line galaxiesobserved.
|BV photometry and radial velocities of southern spiral galaxies|
Multiaperture photoelectric photometry for 119 southern spiral galaxiesand heliocentric velocities for 98 southern spiral galaxies obtainedfrom image-tube spectrograms are presented. The data were collected in1976, 1977, and 1978 at Cerro Tololo Inter-American Observatory. Themagnitude and (B-V) color index are compared with aperture diameter inorder to determine if the present data correlate with previousmeasurements. The comparison reveals that the data correspond. Theinternal measurement error of the radial velocities is estimated; it isobserved that the internal error for one measurement is 41 km/sec.
|Southern Galaxy Catalogue.|
|Redshifts for 228 southern galaxies|
In this paper, new redshifts are presented for 228 galaxies locatedsouth of declination -30 deg. The observations were made with aphoton-counting Reticon detector on the Observatorio Nacional (ON)60-in. telescope. The detector is identical to the one used at MountHopkins for the CfA Redshift Survey, and the redshifts were derivedusing the same data-analysis system. A preliminary comparison withpublished 21-cm redshifts indicates that the velocities have azero-point offset of about -4 km/s, with a typical uncertainty of 40km/s. The observations reported here are the initial results of theON-CfA Redshift Survey currently being undertaken in the southernhemisphere.
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