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Ultraviolet and Optical Spectra of Broadline Radio Galaxies
Peterson, Bradley M.; Wagner, R. Mark; Crenshaw, D. Michael
Near-simultaneous ultraviolet and optical spectra of three broadline radio galaxies (3C 382, 3C 445, and PKS 2349 - 014) have been obtained, and the emission lines of Lyα, Hβ, and Hα have been deconvolved into narrow and broad components; published fluxes for 3C 390.3 are also included in this study. Although the broad Lyα/Hβ ratios in these objec…
Ultraviolet emission lines and optical photometry of the flare star AT Microscopii.
Linsky, J. L.; Marang, F.; Ayres, T. R. +8 more
Ultraviolet spectra of the dwarf flare star binary AT Mic (dM 4.5e+dM 4.5e) were obtained with the IUE spacecraft on three days in September 1985. A high-resolution short-wavelength spectrum was exposed for 25 hours. Simultaneous optical monitoring in the U-band was performed during part of the IUE observations. At the time of observation AT Mic w…
Ultraviolet Spectra of the Narrow-Lined Seyfert Galaxies Markarian 573 and Markarian 1388
MacAlpine, Gordon M.
Ultraviolet spectra, obtained with the IUE satellite, are presented for the unusually narrow-lined Seyfert galaxies Mrk 573 and Mrk 1388. The data support class 2 identifications for both galaxies and also suggest the need for more energetic ionizing radiation in the most recently published Seyfert 2 galaxy photoionization calculation.
The unusual carbon star HD 59643 : alternative models.
Querci, M.; Johnson, H. R.; Eaton, J. A. +2 more
The authors discuss a binary model for the star in which the secondary spectrum is formed in an accretion disk. If this hot, ultraviolet-emitting disk radiates like a 20,000K black-body, it must be ≤0.03 R_sun; across at minimum emission. Large widths of C IV multiplet UV1 on high-resolution spectra indicate its formation in the inner parts of a d…
An Improved Photometric Analysis of SX Aurigae
Peters, Geraldine J.; Linnell, Albert P.; Polidan, Ronald S.
The photometric analysis reported leads to four principal conclusions: 1. The SX Aur system consists of two normal main-sequence stars. The components are very close to the inner Roche limiting surface. 2. The primary component is extremely close to contact with its inner Roche lobe, as well as can be judged from the photometric solution. It is in…
The vanishing shell phase of PLEIONE in the far UV in 1988.
Doazan, V.; Thomas, R. N.; Bourdonneau, B.
Far UV observations made with the IUE in 1988, when the shell spectrum of Pleione was vanishing in the visible region, are compared with previous IUE observations made when the shell was strong (1979) and when it began to weaken (1985). Between the epochs of strong shell and vanishing shell: (1) the apparent continuum level increases in all the ob…
Detection of Extragalactic Absorption in the Ultraviolet Spectrum of the BL Lacertae Object PKS 2155-304
Maraschi, L.; Tanzi, E. G.; Treves, A. +2 more
The complete collection of ultraviolet spectra (1200-3000 A) of PKS 2155-304 taken with IUE in l979-1986 is reanalyzed with the aim of producing a high signal-to-noise ratio spectrum. As a result of co-adding the best exposed spectra a number of absorption lines are found, most of which can be identified with expected interstellar species in our G…
Are tides responsible for enhanced MG II emission in late-type binaries ?
Glebocki, R.; Stawikowski, A.
Mg II h and k fluxes are measured for a homogeneous sample of 30 G III and K III binaries. The spectra have been obtained from the IUE archive and calibrated in absolute units (erg cm-2s-1). Contrary to the generally accepted view that the rate of rotation is responsible for the enhanced chromospheric activity, the Mg II h an…
The Spatial Distribution of Ultraviolet Line and Continuum Emission in Herbig-Haro Objects
Lee, M. G.; Raga, A. C.; Brugel, E. W. +4 more
Using archival IUE data and "monochromatic" CCD images in the optical range, the authors compare the spatial distribution of ultraviolet and optical emission in Herbig-Haro objects. Specifically, they consider the objects HH 1, HH 2, HH 24, HH 32, HH 43, and HH 47. Spatial distributions have been studied in the UV lines C IV 1550, C III] 1909, C I…
An Optical and UV Investigation of the IRAS Seyfert Galaxy 1319-164
Hutchings, J. B.; De Robertis, M. M.; Pitts, Ronald E.
We present optical and UV spectroscopy, and optical-imaging observations of the bright IR-selected Seyfert galaxy 1319 - 164. We find that the nucleus is reddened by E_B-V_ = 0.3 mag, both in the lines and continuum. The galaxy is large and contains little, if any, spiral structure. There are low-brightness structures at about 5" from the nucleus,…