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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 (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39
| Classifications of the Host Galaxies of Supernovae
Classifications on the DDO system are given for the host galaxies of 177supernovae (SNe) that have been discovered since 1997 during the courseof the Lick Observatory Supernova Search with the Katzman AutomaticImaging Telescope. Whereas SNe Ia occur in all galaxy types, it isfound, at a high level of statistical confidence, that SNe Ib, Ic, andII are strongly concentrated in late-type galaxies. However, attentionis drawn to a possible exception provided by SN 2001I. This SN IInoccurred in the E2 galaxy UGC 2836, which was not expected to harbor amassive young supernova progenitor.
| Supernovae 2001eu, 2001fb, 2001fg, 2001fw, and 2001fx
IAUC 7754 available at Central Bureau for Astronomical Telegrams.
| Supernovae 2001ej, 2001fx, and 2001fy
IAUC 7751 available at Central Bureau for Astronomical Telegrams.
| The Durham/UKST Galaxy Redshift Survey - V. The catalogue
We present the radial velocities and blue, optical magnitudes for all ofthe galaxies within the Durham/UKST Galaxy Redshift Survey. Thiscatalogue consists of ~2500 galaxy redshifts to a limiting apparentmagnitude of B_J⋍17 mag, covering a ~1500-deg^2 area around theSouth Galactic Pole. The galaxies in this survey were selected from theEdinburgh/Durham Southern Galaxy Catalogue and were sampled, in order ofapparent magnitude, at a rate of one galaxy in every three. Thespectroscopy was performed at the 1.2-m UK Schmidt Telescope inAustralia using the FLAIR multi-object spectrograph. We show that ourradial velocity measurements made with this instrument have an empiricalaccuracy of +/-150 km s^-1. The observational techniques and datareduction procedures used in the construction of this survey are alsodiscussed. This survey demonstrates that the UKST can be used to make athree-dimensional map of the large-scale galaxy distribution, via aredshift survey to b_J⋍17 mag, over a wide area of the sky.
| 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.
| Imaging of MBG starbursts - II. The nature of the sample
In this paper, broad-band imaging in BVRI is used in parallel withinformation from long-slit spectroscopy and IRAS data to study starformation processes in a sample of 15 MBG (Montreal blue galaxy)starbursts, in order to understand their nature more clearly. Most ofthese galaxies are early-type spirals with disturbed morphologies. Theburst of star formation is concentrated in the nucleus, extending to amean distance of 1.6 kpc from the centre. In the most active cases,ionized gas could be detected up to a substantial fraction of the radiusof the optical surface of the galaxy. We have found evidence suggestingthat the enhancement of star formation in our galaxies is correlated toa higher concentration of gas in the nucleus. No mechanism was clearlyidentified to explain the accretion of gas in this region. Even thoughwe see MBGs at different levels of activity and with differentmorphologies, they present similar characteristics in terms of starformation processes. The peculiar morphologies, the infraredcharacteristics and the net excess of gas in the MBGs compared withgalaxies of the same morphological type suggest that the bursts arerelated to some kind of interaction with other galaxies. We foundnear-constant star formation rates over a period of a few Gyr, which weinterpret as an indication of either long duration bursts (time-scale ofthe order 1Gyr) or a succession of shorter bursts. The concentration ofthe bursts into the circumnuclear regions and their importance in termsof masses of stars created suggest that this particular phenomenon couldrepresent an important phase in the evolution of these galaxies.
| Imaging of MBG starbursts - I. Morphological analysis
We present, in detail, the morphological analysis of a sample of 15galaxies of the Montreal blue galaxy (MBG) survey, based on BVRIimaging. The sample consists of starburst nucleus galaxies, mostly withearly-type morphologies. We fit elliptical isophotes to the images, andanalyse the parameters derived from the fitting procedure, theluminosity profiles, the B-I colour profiles and B-I colour maps.Circumnuclear regions of star formation are identified, correspondingwell to the extended Hα emission measured spectroscopically. Thedimensions of these extended regions are of the order of kiloparsecs.For barred galaxies, the star formation is more concentrated than forunbarred ones, which tend to have extended starbursts. A highinteraction rate for the objects studied is indicated by the frequencyof dust, twisted isophotes, and a wide dispersion of colours (similar toArp-Madore galaxies), which is not correlated with the morphologicaltype. The observed isophotal twists in our sample are related to thepresence of bars, for SBa and later types, or to geometrical decoupling,for S0 and E galaxies. The level of `boxiness' and `discyness' is largerthan that of normal early-type galaxies, reflecting the disturbedmorphology of these objects. The connection of these morphologicalcharacteristics with the observed starbursts is highly probable.
| The Montreal blue galaxy survey. I - First list of ultraviolet-bright candidates
The first results of a UV-bright galaxy survey using theMontreal-Cambridge-Tololo (MCT) plate collection are presented. Visualinspection of 57 CTIO Curtis Schmidt plates, cnvering more than 1300 sqdeg, has resulted in the identification of 95 UV-bright galaxiesbrighter than B = 15.5. Even though 80 percent of these objects are IRASsources, barely 20 percent have their nature already established. Theinitial result of our survey shows that the bulk of our UV-brightcandidates are narrow emission-line galaxies commonly known as starburstor H II galaxies. The fraction of AGNs found is somewhat less than 10percent, but comparable to what has been found by the Markarian survey.
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