Search Publications

Structure and Kinematics of the Broad-Line Regions in Active Galaxies from IUE Variability Data

Koratkar, Anuradha P.; Gaskell, C. Martin

IUE archival data are used to investigate the structure and kinematics of the broad-line regions (BLRs) in nine active galactic nuclei (AGNs). The cross-correlation technique, for unevenly sampled data, advocated by Gaskell and Sparke has been applied to spectra taken between 1978 and 1988. An extensive investigation of the errors has been carried…

An Ultraviolet Atlas of Quasar and Blazar Spectra

York, D. G.; Blades, J. C.; Bohlin, R. C. +1 more

We have constructed an ultraviolet atlas of 69 quasars, blazars, and Seyfert 1 galaxies by combining over 1000 low-resolution spectra drawn from over a decade of observations contained in the IUE data archive. In order to optimize the signal-to-noise ratio, the spectra have been reextracted and co-added. The IUE spectra show that quasars and blaza…

Predicted Profiles of Ultraviolet Interstellar Absorption Lines

York, D. G.; Welty, D. E.; Hobbs, L. M.

In this paper, values of the column density, line width parameter, and velocity are determined for as many components derived from optical interstellar absorption-line profiles of Na I and K I as needed to reproduce the observed high-resolution optical profiles of the D lines of Na I toward eight lightly reddened stars and of the 7698 A line of K …

Fe II Emission Lines. I. Chromospheric Spectra of Red Giants

Judge, P. G.; Jordan, C.

A 'difference filtering' algorithm developed by Ayers (1979) is used to construct high-quality high-dispersion long-wavelength IUE spectra of three giant stars. Measurements of all the emission lines seen between 2230 and 3100 A are tabulated. The emission spectrum of Fe II is discussed in comparison with other lines whose formation mechanisms are…

A Spectrophotometric Atlas of White Dwarfs Compiled from the IUE Archives

Wegner, Gary; Swanson, Steven R.

Ultraviolet spectrophotometric data are presented for 182 subluminous stars, mostly white dwarfs, that have been observed with the low-resolution mode of the IUE satellite since 1978 and for which archived data became available on April 1, 1989. Tables of 20 A binned data are given for all stars. Of these, 133 cover the entire wavelength range of …

The Interoutburst Behavior of Cataclysmic Variables

Szkody, Paula; Mattei, Janet A.; Waagen, Elizabeth O. +1 more

Existing IUE and AAVSO archive data were used to accomplish a large scale study of what happens to the UV flux of accretion disk systems during the quiescent intervals between outbursts, and how it relates to the preceding outburst characteristics of amplitude and width. The data sample involved multiple IUE observations for 16 dwarf novae and 8 n…