Search Publications
A study of UV spectra of zeta Aur/VV CEP stars. IV. System parametersand mass-loss of delta Sge.
Reimers, D.; Schroeder, K. -P.
The orbital elements of the Delta Sge system were improved using new radial velocity measurements. A distance of 170 pc is determined with the assumption that the companion is a mainsequence star with Te = 10,500 K (ca. B9) as found from IUE fluxes. Combining the mass-function with the locations of the components in the HR-diagram, a mass-ratio of…
Evidence for a warm wind from the red star in symbiotic binaries.
Stencel, R. E.; Friedjung, M.; Viotti, R.
A systematic redshift of the high ionization resonance emission lines with respect to the intercombination lines is found from an examination of the ultraviolet spectra of symbiotic stars obtained with IUE. After consideration of other possibilities, this is most probably explained by photon scattering in an expanding envelope optically thick to t…
The ultraviolet variability of the symbiotic star HBV 475.
Schmutz, W.; Nussbaumer, H.
Evidence is presented for the binary nature of the symbiotic star HBV 475 ( = V 1329 Cyg), based on ultraviolet observations taken with the International Ultraviolet Explorer. The fluxes in the emission lines and in the continuum observed during 1978-1982 are related. It is found that the changes in the line and continuum fluxes observed in the fa…
Molecular emission bands in the ultraviolet spectrum of the Red Rectangle star HD 44179.
Sitko, M. L.
New observations of the ultraviolet spectrum of HD 44179 are reported. Absorption due to the CO molecule is present in the spectrum, with NCO ≈ 1018 cm-2. Emission due to either CO or a molecule containing C≡C, C≡N, C-C, and C-H bonds (or both) is also present.
The Seyfert 1 galaxy NGC 4593 - I. Variability of the UV spectrum andphysical conditions in the broad line emitting region.
Penston, M. V.; Clavel, J.; Bergeron, J. +2 more
Results obtained for UV observations of NGC 4593 are reported. The observations were carried out at two epochs using the low resolution spectrograph and the large apertures of the IUE satellite. The data reduction is presented. The properties of the UV continuum as well as its variability are investigated, discussing the selection of continuum win…
IUE observations of the exciting stars of giant HII regions in M 33 :supermassive stars ?
Hutchings, J. B.; Massey, P.
International Ultraviolet Explorer ultraviolet spectrometry is presented for seven bright starlike objects located in large H II regions in M33. Six of these have UV spectra very similar to R136a, the alleged supermassive star in the center of the 30 Dor nebula in the LMC. The UV line spectra suggest temperatures of 40,000-45,000 K. These temperat…
Detection of a stellar prominence of the K supergiant 32 Cyg.
Schroeder, K. -P.
Light curves at various UV wavelengths have been determined from a sequence of high resolution IUE spectra taken around the 1981 eclipse of 32 Cyg B. Attention is given to the first detection of a stellar prominence of the K supergiant, seen as a transient absorption of the B star continuum flux whose mechanism is probably Rayleigh scattering at t…
Outer atmospheres of cool stars. XIV. A model for the chromosphere and transition region of beta Ceti (G9.5 III).
Eriksson, K.; Linsky, J. L.; Simon, T.
In the present chromospheric and transition region model for Beta Ceti, which is consistent with IUE spectra of the Mg II, C II, and C IV resonance lines, the Mg II h and k lines are treated in partial redistribution and the C II and C IV lines in complete redistribution. Computed line fluxes are presented for a range of models to show the range o…
Further ultraviolet observations of interstellar gas associated with the supernova remnant S 147.
Gondhalekar, P. M.; Phillips, A. P.
The IUE satellite was used to obtain high-resolution ultraviolet observations of the star HD 37318 (B0.5Ve) which lies behind the supernova remnant S 147. High-velocity interstellar absorption lines (>VLSR< ≅ + 80 km s-1) were detected which originate in gas associated with the remnant. These lines have been analysed to…
Ultraviolet observations of the transient X-ray sources A0535+26 and A0620-00.
Holm, A. V.; Swank, J. H.; Wu, C. -C. +2 more
Observations of A0535+26 (HDE 245770) by the ANS in September 1975 and March 1976 when it was at the X-ray low state are discussed. Also observed were 58 early-type stars lying within 10 deg of HDE 245770; these stars are used to derive a localized extinction curve. On the basis of the depth of the 2200 A interstellar absorption feature observed i…