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A Search for “Dwarf'' Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies
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-luminosityExpand
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A Search for ``Dwarf'' Seyfert Nuclei. V. Demographics of Nuclear Activity in Nearby Galaxies
We use the sample of emission-line nuclei derived from a recently completed optical spectroscopic survey of nearby galaxies to quantify the incidence of local (z ≈ 0) nuclear activity. ParticularExpand
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Mg II absorption in the spectra of 103 QSOs : implications for the evolution of gas in high-redshift galaxies
Spectra of 103 low- and intermediate-redshift QSOs (roughly half of which are radio sources) have been obtained with a resolution of 4-6 A in order to investigate the statistics of Mg II λλ2796, 2803Expand
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The Opacity of the Lyα Forest and Implications for Ωb and the Ionizing Background
We have measured the distribution function of the flux decrement D = 1 - e-τ caused by Lyα forest absorption from intervening gas in the lines of sight to high-redshift QSOs from a sample of sevenExpand
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The Chandra Deep Survey of the Hubble Deep Field-North Area. II. Results from the Caltech Faint Field Galaxy Redshift Survey Area*
A deep X-ray survey of the Hubble Deep Field-North (HDF-N) and its environs is performed using data collected by the Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-Ray Observatory.Expand
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A Search for “Dwarf” Seyfert Nuclei. IV. Nuclei with Broad Hα Emission
We present the results of an optical spectroscopic survey designed to search for low-luminosity "dwarf" Seyfert nuclei in a magnitude-limited (BT ≤ 12.5 mag) sample of 486 bright, northern galaxies.Expand
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X-ray spectral survey with XMM-Newton of a complete sample of nearby Seyfert galaxies
Results obtained from an X-ray spectral survey of nearby Seyfert galaxies using XMM–Newton are reported. The sample was optically selected, well defined, complete in B  magnitude, and distanceExpand
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The Hubble Space Telescope Quasar Absorption Line Key Project. XIV. The Evolution of Lyα Absorption Lines in the Redshift Interval z = 0-1.5*
We present the results of an analysis of the rate of evolution of the Lyα absorption lines in the redshift interval 0.0 to ~1.5 based upon a sample of 987 Lyα absorption lines identified in theExpand
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A survey of Lyman-limit absorption in the spectra of 59 high-redshift QSOs
The spectra of 59 QSOs are obtained with emission redshifts in the range z = 2.75-4.11 at a resolution of 4 A in the 3150-4700 A range and 6 A in the 4600-7000 A range. The objects constitute anExpand
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