Search Publications
Ultraviolet spectral morphology of the O stars. IV. The OB supergiantsequence.
Walborn, Nolan R.; Nichols-Bohlin, Joy
An atlas of 25 O3 - B8 supergiant spectra in the wavelength ranges 1320 Å - 1580 Å and 1620 Å - 1880 Å is presented, based on high-resolution data from the International Ultraviolet Explorer archives. This remarkably detailed relationship between the stellar-wind profiles and the optical spectral classifications throughout this sequence is emphasi…
The fading of R Coronae Borealis.
Holm, A. V.; Wu, C. C.; Donn, B. +1 more
Using the International Ultraviolet Explorer (IUE) low-resolution spectra were obtained of R CrB, the prototype of its class of variable stars, shortly after the beginning of its 1983-84 minimum and during its rise to maximum again. The behavior of the spectra during the rise to maximum is similar to the behavior of the spectra of RY Sgr during a …
The search for the elusive companion of EG Andromedae.
Pesce, Joseph E.; Stencel, Robert E.; Oliversen, Nancy A.
The authors report observations at opposite quadratures of the interacting symbiotic binary EG And (HD 4174, Period = 470d). After correcting for absolute motion at the system, it appears, surprisingly, that many of the nebular lines arise from material that moves with the red giant star. This fact is used to interpret the observed comp…
The third spectrum of erbium in HR 465.
Cowley, Charles R.; Greenberg, Marcella
The strong presence of Er III in coude spectra of the chemically peculiar (CP) A star HR 465 at the time of rare-earth maximum is discussed. Er III is surely present in other CP stars; earlier studies are confirmed. Er III is only a marginal detection on IUE images of HR 465. A very crude abundance calculation, using an assumed oscillator strength…
Flux distribution in the Algol binary system RW Persei.
Plavec, Mirek J.; Dobias, Jan J.
The authors have obtained IUE low-dispersion spectra and optical ITS scans of the semidetached Algol-type binary system RW Per. They have determined the spectral type of the primary component to be B9.6e, with good accuracy. The spectral type of the cooler component has been determined with less accuracy as K2 III - IV. The system is heavily redde…
A spectrophotometric study of the Algol binary system RX Geminorum.
Plavec, Mirek J.; Dobias, Jan J.
IUE low-dispersion spectra and optical ITS scans of the semidetached Algol-type binary system RX Gem have been obtained. The spectral type of the primary component was determined to be A0, with good accuracy. Since the primary eclipse is only partial, the spectral type of the cooler component has been determined with less accuracy as K2 (+ or - 2)…
The peculiar planetary nebula 75+35 1.
Feibelman, Walter A.
The high galactic latitude planetary nebula 75+35°1 was observed in the low-dispersion mode of the IUE. The UV spectrum is characterized by a strong continuum that matches the energy distribution of a blackbody curve of 90,000K±5000K. A color temperature of 94,000K±4000K is derived. The spectral type mimics that of an O7.5 V star. A very strong N …
Rapid emission-line variations in the UV spectrum of the Wolf-Rayet system HD 90657.
Koenigsberger, G.; Auer, L. H.
The authors report IUE observations of the Wolf-Rayet binary system HD 90657 which indicate that a major change in the properties of the W-R wind occurred on time scales of less than 90 minutes. These are very rapid variations when compared to those resulting from atmospheric eclipse effects, which are also observed in this system. The rapid chang…
Ultraviolet spectra of field horizontal-branch A type stars.
Huenemoerder, D. P.; Philip, A. G. Davis; Hayes, D. S.
The spectra of four FHB stars have been obtained at about 5 Å resolution between λ1200 and λ1900 with the International Ultraviolet Explorer (IUE). The intensity distributions of three of the stars match that of the "FHB distribution" in Huenemoerder et al. (1984). The coolest star of the four, HD 2857, has an ultraviolet distribution that drops o…
The IUE spectrum of the early-type eclipsing binary mu1 Scorpii.
Sahade, Jorge; Garcia, Lia G.
The ultraviolet spectrum of the system Mu1 Scorpii at two phases of the orbital cycle is described. The presence of resonance lines of Si IV and C IV suggests that there are nonthermal sources in the system. The spectrum displays absorption lines that appear to follow the orbital motion of either component. The spectrum also displays sharp absorpt…