Browsing FAS Scholarly Articles by Keyword "Astronomical Spectroscopy"
Now showing items 1-4 of 4
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Damped Lyman-alpha absorption by disk galaxies with large redshifts. III - Intermediate-resolution spectroscopy
(IOP Publishing, 1989)New intermediate-resolution spectroscopy for six members of a sample of 68 moderate- to high-redshift QSOs is presented. Evidence is reported which indicates that seven strong absorption features in the QSO spectra are due ... -
Infrared to x-ray spectral energy distributions of high redshift quasars
(IOP Publishing, 1994)We have observed 14 quasars with z greater than 2.8 with the ROSAT-PSPC, and detected 12 of them, including the z=4.11 quasar 0000-263. We present the first x-ray spectrum of a radio quiet quasar with z greater than 3, ... -
Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. II - an intensive study of NGC 5548 at optical wavelengths
(IOP Publishing, 1991)A large, international program of ground-based optical spectroscopy and photometry of the variable Seyfert 1 galaxy NGC 5548 undertaken in support of an IUE monitoring campaign is described. This contribution presents the ... -
Steps toward determination of the size and structure of the broad-line region in active galactic nuclei. III - Further observations of NGC 5548 at optical wavelengths
(IOP Publishing, 1992)The results of the second year of an intensive ground-based spectroscopic and photometric study of variability in the bright Seyfert 1 galaxy NGC 5548 are reported in order to study the relationship between continuum and ...