NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-08-24 T08:53:46 PDT
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For refcode 2013ApJ...774...67T:
Retrieve 44 NED objects in this reference.
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2013ApJ...774...67T Ultraviolet Emission-line Correlations in HST/COS Spectra of Active Galactic Nuclei: Single-epoch Black Hole Masses Tilton, Evan M.; Shull, J. Michael Abstract. Effective methods of measuring supermassive black hole masses in active galactic nuclei (AGNs) are of critical importance to studies of galaxy evolution. While there has been much success in obtaining masses through reverberation mapping, the extensive observing time required by this method has limited the practicality of applying it to large samples at a variety of redshifts. This limitation highlights the need to estimate these masses using single-epoch spectroscopy of ultraviolet (UV) emission lines. We use UV spectra of 44 AGNs from HST/COS, the International Ultraviolet Explorer, and the Far Ultraviolet Spectroscopic Explorer of the C IV lambda1549, O VI lambda1035, O III] lambda1664, He II lambda1640, C II lambda1335, and Mg II lambda2800 emission lines and explore their potential as tracers of the broad-line region and supermassive black hole mass. The higher signal-to-noise ratio and better spectral resolution of the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) resolve AGN intrinsic absorption and produce more accurate line widths. From these, we test the viability of mass-scaling relationships based on line widths and luminosities and carry out a principal component analysis based on line luminosities, widths, skewness, and kurtosis. At L_1450_ <= 10^45^ erg s^--1^, the UV line luminosities correlate well with Hbeta, as does the 1450 A continuum luminosity. We find that C IV, O VI, and Mg II can be used as reasonably accurate estimators of AGN black hole masses, while He II and C II are uncorrelated. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Key words: galaxies: active, galaxies: fundamental parameters, galaxies: high-redshift, galaxies: Seyfert, quasars: emission lines, ultraviolet: galaxies, ultraviolet: general
Retrieve 44 NED objects in this reference.
Please click here for ADS abstract

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