NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-21 T23:41:35 PDT
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For refcode 1997ApJS..112..315H:
Retrieve 485 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
1997ApJS..112..315H A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies LUIS C. HO AND ALEXEI V. FILIPPENKO Department of Astronomy, University of California, Berkeley, CA 94720-3411 AND WALLACE L. W. SARGENT Palomar Observatory, 105-24 Caltech, Pasadena, CA 91125 Received 1996 December 10; accepted 1997 May 1 ABSTRACT We have completed an optical spectroscopic survey of the nuclear regions (r <~ 200 pc) of a large sample of nearby galaxies. Although the main objectives of the survey are to search for low-luminosity active galactic nuclei and to quantify their luminosity function, the database can be used for a variety of other purposes. This paper presents measurements of the spectroscopic parameters for the 418 emission-line nuclei, along with a compilation of the global properties of all 486 galaxies in the survey. Stellar absorption generally poses a serious obstacle to obtaining accurate measurement of emission lines in nearby galactic nuclei. We describe a procedure for removing the starlight from the observed spectra in an efficient and objective manner. The main parameters of the emission lines (intensity ratios, fluxes, profile widths, and equivalent widths) are measured and tabulated, as are several stellar absorption-line and continuum indices useful for studying the stellar population. Using standard nebular diagnostics, we determine the probable ionization mechanisms of the emission-line objects. The resulting spectral classifications provide extensive information on the demographics of emission-line nuclei in the nearby regions of the universe. This new catalog contains over 200 objects showing spectroscopic evidence for recent star formation and an equally large number of active galactic nuclei, including 46 that show broad H {alpha} emission. These samples will serve as the basis of future studies of nuclear activity in nearby galaxies. Subject headings: galaxies: active-galaxies: fundamental parameters - galaxies: ISM-galaxies: nuclei-galaxies: Seyfert
Retrieve 485 NED objects in this reference.
Please click here for ADS abstract

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