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|The ISOPHOT 170 μm Serendipity Survey II. The catalog of optically identified galaxies%|
The ISOPHOT Serendipity Sky Survey strip-scanning measurements covering≈15% of the far-infrared (FIR) sky at 170 μm were searched forcompact sources associated with optically identified galaxies. CompactSerendipity Survey sources with a high signal-to-noise ratio in at leasttwo ISOPHOT C200 detector pixels were selected that have a positionalassociation with a galaxy identification in the NED and/or Simbaddatabases and a galaxy counterpart visible on the Digitized Sky Surveyplates. A catalog with 170 μm fluxes for more than 1900 galaxies hasbeen established, 200 of which were measured several times. The faintest170 μm fluxes reach values just below 0.5 Jy, while the brightest,already somewhat extended galaxies have fluxes up to ≈600 Jy. For thevast majority of listed galaxies, the 170 μm fluxes were measured forthe first time. While most of the galaxies are spirals, about 70 of thesources are classified as ellipticals or lenticulars. This is the onlycurrently available large-scale galaxy catalog containing a sufficientnumber of sources with 170 μm fluxes to allow further statisticalstudies of various FIR properties.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) areMPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena,Imperial College London.Full Table 4 and Table 6 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (22.214.171.124) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39
|Classifications of the Host Galaxies of Supernovae, Set II|
Classifications on the DDO system are given for an additional 231 hostgalaxies of supernovae that have been discovered during the course ofthe Lick Observatory Supernova Search with the Katzman Automatic ImagingTelescope (KAIT). This brings the total number of hosts of supernovae(SNe) discovered (or independently rediscovered) by KAIT, which have sofar been classified on a homogeneous system, to 408. The probabilitythat SNe Ia and SNe II have a different distribution of host-galaxyHubble types is found to be 99.7%. A significant difference is alsofound between the distributions of the host galaxies of SNe Ia and ofSNe Ibc (defined here to include SNe Ib, Ib/c, and Ic). However, nosignificant difference is detected between the frequency distributionsof the host galaxies of SNe II and SNe IIn. This suggests that SNe IInare generally not SNe Ia embedded in circumstellar material that aremasquerading as SNe II. Furthermore, no significant difference is foundbetween the distribution of the Hubble types of the hosts of SNe Ibc andof SNe II. Additionally, SNe II-P and SNe II-L are found to occur amongsimilar stellar populations. The ratio of the number of SNe Ia-pec tonormal SNe Ia appears to be higher in early-type galaxies than it is ingalaxies of later morphological types. This suggests that the ancestorsof SNe Ia-pec may differ systematically in age or composition from theprogenitors of normal SNe Ia. Unexpectedly, five SNe of Types Ib/c, II,and IIn (all of which are thought to have massive progenitors) are foundin host galaxies that are nominally classified as types E and S0.However, in each case the galaxy classification is uncertain, or newlyinspected images show evidence suggesting a later classification. Amongthese five objects, NGC 3720, the host galaxy of SN 2002at, wasapparently misidentified in the Carnegie Atlas of Galaxies.
|Seeing Galaxies through Thick and Thin. II. Direct Measures of Extinction in Spiral Disks through Spectroscopy of Overlapping Galaxies|
We use slit spectroscopy of overlapping pairs of galaxies to directlydetermine the extinction in disks of foreground spiral galaxies. TheDoppler shifts of pair members are determined via cross-correlation, andtheir relative correlation amplitudes are used to separate theircontributions to the combined spectra in regions of overlap. Thisspectroscopic approach is less subject to stringent symmetry constraintsthan our previous, purely photometric analyses. Extinctions offoreground members were obtained for six of the candidates in our sampleof 18 mostly spiral/spiral pairs, when the signal-to-noise-ratio andvelocity differences were suitable. In agreement with our previousimaging results, we find that the extinction in interarm regions is verymodest, typically AB~0.1 mag (corrected to face-on), whilespiral arms exhibit higher extinctions of ~0.3 mag.
|Parameters of bulges and disks of interacting galaxies|
The photometric structure of 23 interacting galaxies is analyzed. It isshown that equivalent photometric profiles, if used for statisticalanalyses of the global structure of the disks of spiral galaxies, yieldthe same results as major-axis profiles. When analyzing nonaxisymmetricand faint objects, the equivalent profiles should be preferred to boththe major-axis and elliptically averaged profiles. The studies ofintegral characteristics of bulges of interacting spiral galaxies showedthat the parameters of these objects obey the mu_e-gamma_e relation fornormal spirals over a wide range of surface-brightness (~ 10 mag) andlinear-dimension (~ 3x10^2) values. This fact may imply that stronggravitational perturbations have little effect on dense central galaxyregions, leaving the bulges in a state that is very close toequilibrium. The central parts of disks in interacting spirals are, onthe average, ~ 1 mag brighter than the corresponding regions in isolatedgalaxies, which is probably attributable to enhanced star-formationprocess. Integrated photometric parameters of the disks of localinteracting galaxies are similar to those of spiral galaxies ofcomparable size observed at z ~ 1. The latter are also characterized byhigh surface brightness. Among them, interacting or disturbed objectscomprise a sizable fraction. It may be assumed that gravitationalperturbations and external accretion contribute significantly to theobserved evolution of disk parameters in large spiral galaxies, when z ~1.
|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.
|Bright galaxies from WENSS. I. The minisurvey|
A search for bright galaxies associated with radio sources from theWENSS minisurvey has been carried out. A galaxy counterpart was foundfor 402 of almost 10,000 radio sources. Of these a radio and opticallycomplete sample, with a flux density limit at 325 MHz of 30 mJy and alimiting red magnitude of 16, can be constructed, which contains 119galaxies. This paper is the first step of a more general study, in whichwe aim to derive a bright galaxy sample from the entire WENSS survey(which is now available in the public domain) and thus to constructpractically definitive local radio luminosity functions of ellipticaland spiral galaxies. We briefly describe the WENSS minisurvey, and thesteps that are needed for the optical identification of its radiosources. Due to the large numbers of sources involved (over 200,000)completely automated procedures are obviously needed and we discussthese in some detail. It is shown that with modern utilities projects asdescribed here have become quite feasible. Some results (e.g. apreliminary determination of the local radio luminosity function) arepresented. Table 1 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (126.96.36.199) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
|Tidally-triggered disk thickening. II. Results and interpretations.|
We have reported in a previous paper (Paper I, Reshetnikov and Combes,1996A&AS..116..417R) B,V and I band photometric data for a sample of24 edge-on interacting spiral galaxies, together with a control sampleof 7 edge-on isolated galaxies. We discuss here the main result found inthis study: the ratio h/z_0_ of the radial exponential scalelength h tothe constant scaleheight z_0_ is about twice smaller for interactinggalaxies. This is found to be due both to a thickening of the plane, andto a radial stripping or shrinking of the stellar disk. If we believethat any galaxy experienced a tidal interaction in the past, we mustconclude that continuous gas accretion and subsequent star formation canbring back the ratio h/z_0_ to higher values, in a time scale of 1Gyr.
|Interacting System ARP 30|
Arp 30 is a galaxy pair composed of a face-on spiral and an edge-on diskgalaxy. There have been very few observations of Arp 30, probablybecause of its great distance (160 Mpc for H_0_ of 50). We have obtainedCCD images of Arp 30 in the B, V, R, and I bands and a narrow filter atthe redshifted Hα wavelength, J, H, and K images from the KPNO'sSQIID, and optical-red spectra of each galaxy. These results combinedwith IRAS data show that Arp 30 is a moderate starburst system of abouttwice the luminosity of M82 and a total star formation rate of about 18M_sun_/yr. Star formation is occurring in both components of the pairand is most enhanced in the nucleus of the face-on galaxy. The galaxiesappear to be connected by a bridge containing clumpy Hα emission,a feature resembling young star clusters. The structure and starformation enhancement resemble simulations of disk galaxies in theirfirst close pass.
|Tidally-triggered disk thickening. I. Observations.|
As part of an investigation on what effect galaxy interactions have onthe z-structure of the disks of involved galaxies, we present here newphotometric data in the B, V, I passbands for a sample of 24 interactingsystems and 7 non-interacting galaxies. Isophotes, total magnitudes andcolours of all sample galaxies (67) are determined. Our estimates andthe comparison with the published results show that the accuracy of ourphotometry is about 0.15mag.
|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.
|A photometric study of interacting galaxies. 2: Analysis of the results|
We present the results of a detailed photometric study in theRC band of 73 galaxies in close interacting systems. Thesample for this study was selected mainly from the Atlas of PeculiarGalaxies by Arp on the basis of the optical morphology of galaxies. Theobserved systems exhibit: an excess of early type spirals (Sa) anddeficiency of late type ones (Sm/Irr), and excess of brighter galaxiesas compared with field galaxies. From the decomposition of theequivalent profiles we found the following principal results: (a)Interacting ellipticals and bulges of SO galaxies are systematicallydisplaced in the plane mue - Re from the relationfor normal galaxies. This displacement may be explained in terms ofbulges of interacting galaxies being more compact. (b) Bulges ofinteracting spirals are located in the effective parameters plane in thesame region of bulges of non-interacting galaxies. (c) Disks of stronglyinteracting spirals are 2-3 times thicker as compared with disks ofnormal galaxies. (d) The central surface brightnesses (mu0 ofthe disks of interacting galaxies are, on average, brighter than forfield spirals. (e) There is no clear dependence of the globalphotometric characteristics of galaxies on the interaction strength.There is a weak tendency for galactic disks to be slightly brighter andshorter than in strongly interacting systems.
|Northern dwarf and low surface brightness galaxies. II - The Green Bank neutral hydrogen survey|
The paper reports neutral hydrogen observations of a large sample ofdwarf and other low surface brightness galaxies. A detailed discussionand error analysis of the observations are presented, and spectra aredisplayed for 329 galaxies detected for the first time, or detected withsubstantially better signal-to-noise ratios than achieved previously.The positions on the sky of 667 galaxies meeting the present selectioncriteria north of delta = 38 deg are shown. The distribution of theredshifts of galaxies detected at Green Bank is illustrated. The GreenBank detections tapered off strongly below the median H I flux of 3.7 Jykm/s detected at Arecibo: only 12 percent of the Green Bank sample wasdetected with smaller fluxes.
|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.
|Photoelectric Observations of Interacting and Compact Galaxies|
|Double galaxy investigations. I - Observations|
Redshift information from 240 A/mm spectrograms is presented for 370double arcsec galaxy systems from the Karachentsev (1972) catalog,including all pairs in that catalog with separation less than 80 arcsec.An extensive error discussion utilizing internal and external (21 cm)comparisons provides calibration of systematic error and determines theuncertainty for a typical high weight optical redshift to be plus orminus 65 km/sec. Internal differential redshifts within single spectrausing common lines achieve accuracies of 18-30 km/sec, depending uponseparation, and are available for about 200 pairs. Extensive informationon emission and other properties is also provided.
|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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