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Wind Variability in the Large Magellanic Cloud B[e] Supergiant HD 34664
Clayton, G. C.; Schulte-Ladbeck, R. E.
We present optical linear spectropolarimetry of the B[e] supergiant HD 34664. The polarization and position angle display significant spectral features which correspond to the Hα and Hβ emission lines. We use the line polarizations to separate the interstellar foreground polarization from the intrinsic polarization of HD 34664. The intrinsic polar…
Deep Hubble Space Telescope Imaging of 53WO44: an SO Radio Galaxy at z=0.311
Keel, William C.; Windhorst, Rogier A.
We present images with the Wide-Field Camera (WFC) and Faint-Object Camera (FOC) of the radio galaxy 53W044, as part of a morphological study of the faint radio-source population. The WFC images are used to examine the structure of the galaxy, and show evidence for a significant disk (contributing 18%-20% of the light in the observed V and I bands…
The Onset of Wolf-Rayet Wind Outflow and the Nature of the Hot Component in the Symbiotic Nova PU Vulpecula
Sion, Edward M.; Shore, Steven N.; Scheible, Maureen P. +1 more
We have analyzed temporal variations in the far ultraviolet He II (1640), Si IV (1393, 1402), and C IV (1548, 1550) line profiles in eight high dispersion, International Ultraviolet Explorer Short Wavelength Prime spectra of the symbiotic nova PU Vul by comparatively examining these profiles on a common velocity scale. We see clear evidence of the…
Interstellar Extinction Toward the CAS OB6 Association: Where is the Dust?
Clayton, Geoffrey C.; Hanson, Margaret Murray
We have completed a multiband (ultraviolet, optical, and near-infrared) study of the interstellar extinction properties of nine massive stars in IC 1805 and IC 1848, which are both part of Cas OB6 in the Perseus spiral arm. Our analysis includes determination of absolute extinction over the wavelength range from 3 micrometers to 1250 A. We have at…
The Orbit and Companion of the Cepheid S SGE: A Probable Triple System
Evans, Nancy R.; Welch, Douglas L.; Slovak, Mark H. +2 more
New radial velocities for the classical Cepheid S Sge have been obtained and combined with previous observations to derive a new orbit. The revised orbital elements are: gamma, -10.3 +/- 0.4 km/s; K, 15.5 +/- 0.2 km/s; e, 0.23 +/- 0.02; omega, 203.1 +/- 4.2 deg; T0, 39902.3 +/- 6.6 JD; P, 675.79 +/- 0.18 days; f(m), 0.239 +/- 0.010 solar masses; a…
Near-Infrared and Ultraviolet Spectrophotometry of the Young Planetary Nebula Hubble 12
Feibelman, Walter A.; Erwin, Peter; Rudy, Richard J. +2 more
The young planetary nebula Hubble 12 is observed using near-IR and UV spectrophotometry. The brightness of the O I lines, which is greater than in any other planetary nebula yet measured, indicates that fluorescent excitation by stellar continuum is the principal mechanism generating these lines. Extinction, electron density, and electron temperat…
A New Look at the Dust Toward Omicron Persei and Sigma Scorpii With the International Ultraviolet Explorer
Clayton, Geoffrey C.; Hanson, Margaret M.
The first IUE low dispersion spectra for Omicron Persei and Sigma Scorpii have been obtained and extinction curves from 1150 to 3250 A are presented. It is of interest to consider Omicron Persei and Sigma Scorpii dust in the context of the average extinction law of Cardelli et al (1989), here referred to as 'CCM', which depends on the R(v) paramet…
Luminosities for Two Yellow Supergiants: Non-variables and the Instability Strip
Evans, Nancy R.
The luminosities for two yellow supergiants HD 183864 and Psi And = HD 223047 are determined from the IUE spectra of their hot companions. The absolute magnitudes of HD 183864 and HD 223047 are -2.3 and -2.1 mag, respectively, and their companions have spectral types of A0.0 V and B8.8 V. The companion of Psi And is compatible with the orbital mot…
On the Chromosphere of 32 Cygni
Eaton, Joel A.
Archival IUE observations and new optical spectra of atmospheric eclipses are analyzed to define the physical properties of the chromosphere of 32 Cyg. Excitation temperatures clearly rise with height in the chromosphere, starting at about 5000 K close to the star. Temperatures in the range 12,000-17,000 K are attained high in the chromosphere, al…
31 Cygni: The B Star and the Wind
Eaton, Joel A.
I have followed photospheric and wind absorptions in International Ultraviolet Explorer (IUE) spectra over much of the orbit of this K4 Ib+B3-4 binary system, using interstellar lines to transform all the velocities to a scale with the interstellar medium at -10.1 km/s. Results are as follows: Interstellar Fe II lines give NL (Fe(+)) = 1-2 x 10