Numerous Proplyd Candidates in the Harsh Environment of the Carina Nebula
We report the discovery of dozens of compact objects in the CarinaNebula (NGC 3372) that closely resemble proplyds (photoablatingprotoplanetary disks and dark silhouette disks) seen previously in theOrion Nebula. This is the first detection of a large number of suchobjects outside Orion. They imply that low- and intermediate-mass starformation is proceeding actively in Carina, despite threateningconditions imposed by very hot massive stars. The proplyd candidatesthat we have detected are larger than those in Orion but more compactthan irregular molecular globules within the H II region. Smallerproplyds may still be lurking in Carina, waiting to be discovered. Orionapparently lacks objects of comparable size, and we consider severalexplanations. Larger proplyds may come from larger and more massivecircumstellar disks surrounding young Herbig Ae/Be stars that should benumerous in Carina. Alternatively, far-UV radiation from the massivestar η Car may have, in the recent past, enhanced photoablation andexpanded proplyd ionization fronts. Some unusual proplyd candidates mayalso imply that time-dependent effects associated with η Car'scurrent evolutionary state may be critical.
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A search for Low Surface Brightness galaxies in the near-infrared. II. Arecibo H I line observations
A total of 367 Low Surface Brightness galaxies detected in the 2MASSall-sky near-infrared survey have been observed in the 21 cm H I lineusing the Arecibo telescope. All have a Ks-band mean centralsurface brightness, measured within a 5'' radius, fainter than 18 magarcsec-2. We present global H I line parameters for the 107clearly detected objects and the 21 marginal detections, as well asupper limits for the undetected objects. The 107 clear detectionscomprise 15 previously uncatalogued objects and 36 with a PGC entryonly.Tables \ref{tab2}, \ref{tab4}, \ref{tab4b}, 5a, 5b and Figs. 2, 3 areonly available in electronic form at http://www.edpsciences.org
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A search for Low Surface Brightness galaxies in the near-infrared. I. Selection of the sample
A sample of about 3800 Low Surface Brightness (LSB) galaxies wasselected using the all-sky near-infrared (J, H and Ks-band)2MASS survey. The selected objects have a mean central surfacebrightness within a 5'' radius around their centre fainter than 18 magarcsec-2 in the Ks band, making them the lowestsurface brightness galaxies detected by 2MASS. A description is given ofthe relevant properties of the 2MASS survey and the LSB galaxy selectionprocedure, as well as of basic photometric properties of the selectedobjects. The latter properties are compared to those of other samples ofgalaxies, of both LSBs and ``classical'' high surface brightness (HSB)objects, which were selected in the optical. The 2MASS LSBs have aBT_c-KT colour which is on average 0.9 mag bluerthan that of HSBs from the NGC. The 2MASS sample does not appear tocontain a significant population of red objects.All tables and Figs. 2a-c are only available in electronic form athttp://www.edpsciences.org
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The UZC-SSRS2 Group Catalog
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
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Compact groups in the UZC galaxy sample
Applying an automatic neighbour search algorithm to the 3D UZC galaxycatalogue (Falco et al. \cite{Falco}) we have identified 291 compactgroups (CGs) with radial velocity between 1000 and 10 000 kms-1. The sample is analysed to investigate whether Tripletsdisplay kinematical and morphological characteristics similar to higherorder CGs (Multiplets). It is found that Triplets constitute lowvelocity dispersion structures, have a gas-rich galaxy population andare typically retrieved in sparse environments. Conversely Multipletsshow higher velocity dispersion, include few gas-rich members and aregenerally embedded structures. Evidence hence emerges indicating thatTriplets and Multiplets, though sharing a common scale, correspond todifferent galaxy systems. Triplets are typically field structures whilstMultiplets are mainly subclumps (either temporarily projected orcollapsing) within larger structures. Simulations show that selectioneffects can only partially account for differences, but significantcontamination of Triplets by field galaxy interlopers could eventuallyinduce the observed dependences on multiplicity. Tables 1 and 2 are onlyavailable in electronic at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.125.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/391/35
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The fundamental plane of early-type galaxies: stellar populations and mass-to-light ratio.
We analyse the residuals to the fundamental plane (FP) of ellipticalgalaxies as a function of stellar-population indicators; these are basedon the line-strength parameter Mg_2_ and on UBVRI broad-band colors, andare partly derived from new observations. The effect of the stellarpopulations accounts for approximately half the observed variation ofthe mass-to-light ratio responsible for the FP tilt. The residual tiltcan be explained by the contribution of two additional effects: thedependence of the rotational support, and possibly that of the spatialstructure, on the luminosity. We conclude to a constancy of thedynamical-to-stellar mass ratio. This probably extends to globularclusters as well, but the dominant factor would be here the luminositydependence of the structure rather than that of the stellar population.This result also implies a constancy of the fraction of dark matter overall the scalelength covered by stellar systems. Our compilation ofinternal stellar kinematics of galaxies is appended.
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A Catalog of Stellar Velocity Dispersions. II. 1994 Update
A catalog of central velocity dispersion measurements is presented,current through 1993 September. The catalog includes 2474 measurementsof 1563 galaxies. A standard set of 86 galaxies is defined, consistingof galaxies with at least three reliable, concordant measurements. It issuggested that future studies observe some of these standard galaxies sothat different studies can be normalized to a consistent system. Allmeasurements are reduced to a normalized system using these standards.
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ROSAT X-ray survey of an area 10 degrees square around the active radio galaxy Centaurus A
Diffuse X-ray material extends in an irregular, broad filament for morethan 5 degrees north east of the giant radio elliptical, NGC 5128 (CenA). In the opposite direction the X-ray extension is clearly traced forabout 2 degrees, making an overall line of X-rays of greater than 7degon the sky originating from Cen A. The direction of this line coincidesalmost exactly with the direction of the X-ray jet, and its associatedradio jet, in the interior of Cen A. At a slightly different angle,within the accuracy of measurement along the X-ray counter jet, isencountered the radio and X-ray galaxy NGC 5090. Its presence in theX-ray ejection from Cen A supports the precedent from other associationsthat NGC 5090 is physically associated with Cen A. In the hardest X-raysthere is some indication that the radio lobes from Cen A are edgebrightened. Positions and known identifications of sources in the fieldare given. Some preliminary estimates of the properties of thisextensive X-ray material which has apparently been ejected from thisactive galaxy are given.
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A near-infrared imaging survey of interacting galaxies - The small angular-size ARP systems
Near-IR images of a large sample of interacting galaxies selected fromthe Atlas of Peculiar Galaxies by Arp (1966) have been obtained.Approximately 180 systems have been imaged in at least two, and usuallythree of the standard JHK bands. The survey and the observing and datareduction procedures, are described, and contour plots and aperturephotometry are presented. Future papers will analyze the imaging data bygroupings based on interaction type, stage, and progenitors. The goalsof the analysis are to explore the relationships between galaxyinteractions, activity, and morphology by studying the structure of thenear-IR luminosity distribution, where extinction effects are muchreduced relative to the optical and the major stellar mass component ofgalaxies dominates the observed light.
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Low-frequency radio continuum evidence for cool ionized gas in normal spiral galaxies
A 57.5-MHz survey of a total of 133 (mostly late-type spiral) galaxieshas resulted in the detection of 68. The ratio of observed intensitiesto intensities extrapolated from higher-frequency measurements is wellcorrelated with the axial ratio of the observed galaxies, and isinterpretable due to increasing free-free absorption of nonthermalemission in galaxy disks with increasing tilt. The implied free-freeabsorption is interpreted as due to the pervasive presence of a clumpymedium of well-mixed, nonthermally emitting, thermally absorbing gaswith small filling factor.
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Groups of galaxies in the Center for Astrophysics redshift survey
By applying the Huchra and Geller (1982) objective group identificationalgorithm to the Center for Astrophysics' redshift survey, a catalog of128 groups with three or more members is extracted, and 92 of these areused as a statistical sample. A comparison of the distribution of groupcenters with the distribution of all galaxies in the survey indicatesqualitatively that groups trace the large-scale structure of the region.The physical properties of groups may be related to the details oflarge-scale structure, and it is concluded that differences among groupcatalogs may be due to the properties of large-scale structures andtheir location relative to the survey limits.
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Spectroscopic analysis of KISO ultraviolet-excess galaxies
Spectroscopic properties of 57 ultraviolet-excess galaxies (KUGs), whichwere selected from the Kiso survey by Takase et al. (1983), arepresented. Observational data are low-resolution spectra taken with theCassegrain image-intensifier spectrograph of the Okayama 188-cmtelescope. About 85 percent of this sample exhibit conspicuous emissionlines similar to galactic nebulae. The radial velocities of the objectshave been obtained from their emission lines as accurate at + or - 90km/s. The absolute magnitudes estimated from the radial velocitiesindicate that a wide range exists in blue luminosity of irregulargalaxies, and that this sample includes less luminous spiral galaxies.Equivalent widths of emission lines have been measured against the localcontinuum, and a diagram of the emission line ratio of forbidden O III5007 A/H-beta versus forbidden N II 6584 A/H-alpha is applied toclassify these objects. The diagram suggests that most KUGs are thosewhich have giant H II regions or H II complexes, where bursts of starformation take place on enhanced scales. On the other hand, Seyfertgalaxies and other kinds of peculiar galaxies are possibly included asminor members of KUGs. It is shown that the Kiso survey includes farmore ultraviolet-excess galaxies of fainter magnitudes than the firstMarkarian survey.
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KISO survey for ultraviolet-excess galaxies. IV
Presented here are the fourth list and identification charts of theultraviolet-excess galaxies which have been detected on the multicolorplates taken with the Kiso Schmidt telescope for 10 survey fields. Inthe sky area of some 300 square degrees 752 objects are cataloged downto the photographic magnitude of about 18.
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Low-resolution spectra of KISO ultraviolet-excess galaxies
The paper presents low-resolution spectra of 57 ultraviolet-excessgalaxies, which are analyzed by Maehara et al. (1986b). The observationwas made with the Cassegrain image-intensifier spectrograph attached tothe Okayama 188-cm telescope. The measurement was carried out with theMD-III microphotometer and the spectral tracings were plotted with theOKITAC-50/40 minicomputer in the logarithmic intensity scale. It isshown that about 85 percent of this sample exhibits conspicuous emissionlines similar to galactic H II regions or emission nebulae.
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A radio observation of ultraviolet-excess galaxies
A deep radio observation of ultraviolet-excess galaxies was made withthe Nobeyama 45-m radio telescope at 10 GHz. Of thirty-eight objectsobserved, eight were detected beyond the 3sigma limit, and eight weresuspected. Integrated radio emission from these galaxies is fairlystrong and nonthermally dominant in this wavelength range.
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A catalog of stellar velocity dispersions. I - Compilation and standard galaxies
A catalog of central stellar velocity dispersion measurements ispresented, current through June 1984. The catalog includes 1096measurements of 725 galaxies. A set of 51 standard galaxies is definedwhich consists of galaxies with at least three reliable, concordantmeasurements. It is suggested that future studies observed some of thesestandard galaxies in the course of their observations so that differentstudies can be normalized to the same system. Previous studies arecompared with the derived standards to determine relative accuracies andto compute scale factors where necessary.
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An observational study of the dynamics of binary galaxies
The single velocity measurement rms error value in the present set ofradial velocities for all galaxies in the Turner (1976) catalog of 156binary systems is estimated t be 29 km/sec. Typical velocity differencesare very small, with half of the 55 systems in the subsample of isolatedspiral-spiral pairs (the most reliable set of 'pure' binaries) havingmeasured velocity differences of less than 75 km/sec. By means of MonteCarlo simulations of scale-free ensembles of binary galaxies, it ispossible to show that the present data's independence of eitherluminosity or projected separation is inconsistent both with thehypothesis that the mass of binary systems increases linearly withluminosity, and that galaxies in pairs may effectively be treated aspoint masses. The data favor models in which galaxies interact through aquasi-isothermal potential only weakly depending on luminosity.
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The Case low-dispersion northern sky survey. I
Positions, estimated magnitudes, and finding charts (when necessary) areprovided for 71 blue and/or emission-line galaxies, probable H IIregions in four galaxies, 59 blue and/or emission-line stellar objectsincluding QSO candidates, and 28 known and probable blue stars in theregion where alpha is between 8h45m and 10h50m and delta is between+29.0 deg and 33.0 deg (1950). The objects, whose blue magnitudes rangefrom 13 to 18, were identified on low-dispersion, objective-prism platestaken with the Burrell Schmidt telescope at Kitt Peak and are theinitial fruits of a survey that will ultimately cover the northern skywithin the boundaries where b and delta are both greater than +30 deg.
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Atlas of interacting galaxies, Part. II and the concept of fragmentation of galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...28....1V&db_key=AST
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Catalogue of UBV photometry and MK spectral types in open clusters, second edition
Not Available
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Binary galaxie. I. A well-defined statistical sample.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJ...208...20T&db_key=AST
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Etude spectroscopique de quelques galaxies compactes.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&A....33..113C&db_key=AST
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Atlas of Peculiar Galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966ApJS...14....1A&db_key=AST
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