Search Publications
The eclipse of epsilon Aurigae in the ultraviolet.
Ferluga, S.; Hack, M.; Boehm, C.
Ultraviolet low-resolution spectra of Epsilon Aurigae (F0Ia +) have been taken with IUE during the partial and total phase of the present eclipse; they are compared with a set of corresponding pre-eclipse spectra. The following conclusions are derived. A hot component, dominant in far UV, is associated with the extended body that eclipses the prim…
The UV spectrum of the Seyfert 1 galaxy NGC 7469.
Westin, B. A. M.
Results from an investigation of thirty-two IUE spectra of the Seyfert 1 galaxy NGC 7469 are presented. During the observation period, from June 1978 to December 1982, the continuum at 1500 Å (observed wavelength) has been found to vary by a factor of about two. The strong emission lines are broad (FWZI 10,000 - 25,000 km s-1) and asymm…
The presence of Si3+ and C3+ in the wind of AB Aur.
Talavera, A.; Catala, C.
The Herbig Ae variable AB Aur (spectral type A0) exhibits a line spectrum characteristic of a stellar wind. IUE observations of the Si IV and C IV resonance lines in AB Aur are reported. These lines are strong and in absorption. Two models can explain the presence of Si3+ and C3+ in the wind of AB Aur: a "remote chromosphere"…
Accretion of mass in Algol.
Molaro, P.; Cugier, H.
Several high resolution IUE spectra of Algol taken in 1978 and 1979 are analysed. Variable additional absorption components for the ultraviolet resonance lines of Mg II, Al III, and Si IV are detected. The additional components show eclipsing effects indicating that they originate in a region near the primary star, Algol A. Moreover, their behavio…
The stellar population of the nucleus of M 33 from an analysis of itslambda-lambda 1200-3000 A spectrum.
Benvenuti, P.; Dodorico, S.; Ciani, A.
The λλ1200 - 3000 Å spectrum of the nucleus of M33 is used in conjunction with U, B, V photometry as input to a linear programming method to determine the stellar population of the system. No astrophysical constraints but modifications in the stellar library (which includes Population II objects) were used to explore different evolutionary histori…
Detection of diffuse LY alpha emission from cD galaxy in Abell 1795.
Norgaard-Nielsen, H. U.; Jorgensen, H. E.; Hansen, L.
The authors report the discovery of diffuse Lyα emission from the cD galaxy in Abell 1795 which has a high X-ray derived mass accretion rate. The Lyα emission coincides with the main optical filamentary structures and the Lyα/Hβ ratio is close to the recombination v…
Mass loss from the central star of NGC 3242.
Pottasch, S. R.; Hamann, W. -R.; Kudritzki, R. -P. +1 more
The central star of NGC 3242, which was classified to be of "continuous type" before Kudritzki et al. (1981) discovered and analysed photospheric absorptions, has been observed with IUE in high resolution. The N V resonance doublet exhibits a weak P Cygni profile with photospheric components. Theoretical profiles are obtained from comoving-frame c…
A study of the Herbig Ae-type stars UX Ori and CD -44°3318 based on IUE spectra, and on visual and infrared photometry.
Djie, H. R. E. Tjin A.; Remijn, L.; Thé, P. S.
Far ultraviolet spectra of the two Herbig Ae stars UX Ori and CD -44°3318 are used to derive spectral types A2 III for UX Ori, and A0 - 1 III for CD -44°3318. The spectral energy distributions are in agreement with that of a Kurucz model with Teff = 9500K and log g = 4.0. In the near infrared both stars have a large excess of radiation,…
Abrupt changes in the C IV resonance lines of theta CR B.
Stalio, R.; Doazan, V.; Thomas, R. N. +2 more
It is noted that the Theta CrB far-UV spectrum changes from conspicuous presence, to complete disappearance, to reappearance at a higher velocity than the previous one, have occurred with a phase lag of about 3 years after the disappearance of a weak shell phase of short duration which was observed in the visible in 1979. This sequence is interpre…
Visual and ultraviolet spectrum of the eclipsing binary V367 Cygni.
Hack, M.; Engin, S.; Yilmaz, N.
V 367 Cyg is a single spectrum eclipsing binary (P = 18.6 d) classified as Beta Lyrae type. Spectroscopic observations during two successive cycles confirm previous studies and indicate that the shell spectrum does not vary greatly and does not present appreciable expansional velocity. The radial velocity of the shell lines may be explained by a r…