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|Southern Isolated Galaxy Triplets|
Seventy-six isolated triple systems of galaxies with declinatiosnδ<-3° were selected using ESO/SERC and POSS-I sky surveydata. The equatorial coordinates, configuration types, angular sizes,component angular separations, component morphological types, totalmagnitudes, and other parameters are reported for each triplet.Radial-velocity estimates are available for all components in 33 of the76 triplets. The median values of the main dynamicalparametersradial-velocity dispersion, mean harmonic radius,absolute magnitudes of member galaxies, and mass-to-luminosityratiosare similar to those obtained earlier for 83 isolatedtriple systems with δ>-3°.
|Tidal disruption rates of stars in observed galaxies|
We derive the rates of capture Nsolar of main-sequence turn-off stars bythe central massive black hole in a sample of galaxies from Magorrian etal. The disruption rates are smaller than previously believed with solarN ~ 10^-4-10^-7 per galaxy. A correlation between solarN and black holemass M is exploited to estimate the rate of tidal disruptions in thelocal Universe. Assuming that all or most galaxies have massive blackholes in their nuclei, this rate should be dominated by sub-L_*galaxies. The rate of tidal disruptions could be high enough to bedetected in supernova (or similar) monitoring campaigns - we estimatethe rate of tidal disruptions to be 0.01-0.1 times the supernova rate.We have also estimated the rates of disruption of red giants, which maybe significant (solar N >= 10^-4 yr^-1 per galaxy) for M >= 10^8M_solar, but are likely to be harder to observe - only of order 10^-4times the supernova rate in the local Universe. In calculating capturerates, we advise caution when applying scaling formulae by otherauthors, which are not applicable in the physical regime spanned by thegalaxies considered here.
|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.
|The relationship between the radio and far-infrared emission in IRAS galaxies - VLA observations of a large well-defined sample at 1420 MHz|
An examination of VLA observations at 1420 MHz of a well-defined sampleof 156 IRAS galaxies reveals a strong correlation between the radio andfar-infrared emission from IRAS galaxies. The flux density ratio isfound to have a constant value of -4.82. The results suggest that thenonthermal radio emission is closely related to the current level ofstar formation, and that the star formation region in most IRAS galaxiesis confined to the central few kpc of the galaxy.
|The Identification of IRAS Point Sources - Part One - a 304-DEGREE Field Centred on the South Galactic Pole|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986MNRAS.223..279W&db_key=AST
|Southern Galaxy Catalogue.|
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