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|Radio Continuum and Far-infrared Emission from the Galaxies in the Eridanus Group|
The Eridanus galaxies follow the well-known radio-FIR correlation. Themajority (70%) of these galaxies have their star formation rates belowthat of the Milky Way. The galaxies that have a significant excess ofradio emission are identified as low luminosity AGNs based on theirradio morphologies obtained from the GMRT observations. There are nopowerful AGNs (L20 cm>1023WHz-1) in the group. The twomost far-infrared and radio luminous galaxies in the group have opticaland HI morphologies suggestive of recent tidal interactions. TheEridanus group also has two far-infrared luminous but radio-deficientgalaxies. It is believed that these galaxies are observed within a fewMyr of the onset of an intense star formation episode after beingquiescent for at least a 100 Myr. The upper end of the radio luminositydistribution of the Eridanus galaxies (L20 cm1022WHz-1) isconsistent with that of the field galaxies, other groups, and late-typegalaxies in nearby clusters.
|The Southern Sky Redshift Survey|
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
|Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies|
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
|ROSAT All-Sky Survey observations of IRAS galaxies. I. Soft X-ray and far-infrared properties|
The 120 000 X-ray sources detected in the RASS II processing of theROSAT All-Sky Survey are correlated with the 14 315 IRAS galaxiesselected from the IRAS Point Source Catalogue: 372 IRAS galaxies showX-ray emission within a distance of 100 arcsec from the infraredposition. By inspecting the structure of the X-ray emission in overlayson optical images we quantify the likelihood that the X-rays originatefrom the IRAS galaxy. For 197 objects the soft X-ray emission is verylikely associated with the IRAS galaxy. Their soft X-ray properties aredetermined and compared with their far-infrared emission. X-ray contourplots overlaid on Palomar Digitized Sky Survey images are given for eachof the 372 potential identifications. All images and tables displayedhere are also available in electronic form.
|An image database. II. Catalogue between δ=-30deg and δ=70deg.|
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
|The Montreal Blue Galaxy survey. 2: Second list of UV-bright candidates|
We present and discuss the second list of the Montreal Blue Galaxysurvey. Following the inspection of 71 plates, we found 237 newcandidates with B less than 15.5. 73 percent of them are also detectedby Infrared Astronomy Satellite (IRAS). Spectrophotometry was carriedout, at medium resolution, for a subset of 40 objects leading to theidentification of three new AGNs and producing 13 new radial velocities.Spectral classification of our candidates confirms our previous findingthat the majority of our candidates are starburst nucleus galaxiessimilar to the objects studied by Balzano in 1983. Our survey is biasedagainst the high excitation starburst H II galaxies and the LINERgalaxies. Metallicities of our galaxies are found to be from log(O/H)=8.4 to 9.0, which suggests galaxies in advanced stages of chemicalevolution.
|The morphological catalogue of galaxies equatorial survey|
We present 865 redshifts of galaxies located in the equatorial stripdelta between -17.5 deg and -2.5 deg in the right ascension rangebetween 20 h and 5 h. Redshifts have been obtained for the completesample of all 833 galaxies in the Morphological Catalog of Galaxies withmagnitudes brighter than m = 14.5 (corresponding approximately tom(Zwicky) = 15.0). This sample also includes three galaxies from othersources with more reliable magnitudes, satisfying this limit, and 29fainter galaxies, usually companions of the galaxies in the magnitudelimited sample. Our maps of a very large volume of nearby spacedemonstrate a variety of coherent large scale structures which includelarge voids, 20-50/h Mpc in diameter and large walls at least 70/h Mpcacross.
|Warm IRAS sources. II - Optical spectroscopy of objects from the point source catalog|
Optical spectra are presented for a sample of 563 high latitude IRASsources exhibiting relatively warm 25-60 micron colors, with a view tothe efficient identification of Seyfert galaxies. Spectroscopic data areobtained on 358 extragalactic objects. The present census is consistentwith an obscuration scheme for producing both types of Seyfert objectfrom a single parent population, although the origin of excess cool IRradiation from many Seyferts remains unclear.
|Warm IRAS sources. I. A. Catalogue of AGN candidates from the point source catalog|
It was previously shown that a blue (warm) 60 to 25 micron infraredcolor provides a powerful parameter for discriminating between AGNs andnormal galaxies, and that the far-IR spectrum is therefore an efficienttool for finding new AGNs. A list of such AGN candidates based on warmIR sources from the IRAS Point Source Catalogue (PSC) is presented here.Identification data and finding charts are also given. In addition, thelist of warm IRAS sources is supplemented by a compendium of data fromthe IRAS PSC on detected sources identified with previously known AGNswhose infrared spectra do not bring them within this color selectioncriterion.
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