Search Publications
The visible and infrared extinction law and the gas-to-dust ratio in the Small Magellanic Cloud.
Bouchet, P.; Lequeux, J.; Prevot, L. +2 more
Photometric observations in the UBVJHK bands have been made for 23 O-B3 stars in the Small Magellanic Cloud, for which the MK spectral type and luminosity class have been determined. Also derived from these data are the extinction curve in the visible and the near-infrared. This curve is very close to the curves in the Galaxy and the Large Magella…
The hybrid spectrum of the LMC hypergiant R 126.
Stahl, O.; Leitherer, C.; Zickgraf, F. -J. +2 more
An extensive spectroscopic (1150 - 6700 Å) and photometric (UBVRIJHKLMN) study of the peculiar LMC hypergiant R126 has been carried out. The authors derive stellar parameters Teff = 22,500K, R = 72 R_sun; and Mbol = -10.5. The corresponding spectral type is B0.5 Ia+. An estimate of the initial and present mass lead…
UV-bright stars in galactic globular clusters, their far-UV spectra and their contribution to the globular cluster luminosity.
de Boer, K. S.
Ultraviolet-bright stars in 7 galactic globular clusters have been observed with 4 - 7 Å spectral resolution between 1150 Å and 3200 Å. The UV-bright stars, which are in the post-AGB (PAGB) phase of evolution, have effective temperatures between 19,000 and 35,000K, and have luminosities of about 103.3L_sun;. They generate on average abo…
The massive wind of S Dor.
Waters, L. B. F. M.; Stahl, O.; Leitherer, C. +4 more
Photometric and spectroscopic observations and UV spectrograms of the variable star S Dor are presented. The equipment used to obtain these data are described. The pseudophotosphere indicated by the absorption lines is examined; pulsation-like motions in the pseudophotosphere are detected. The UV data, which are characterized by Fe II and ionized …
The ejection of shells in the stellar wind of the hypergiant P Cygni (B1Ia+).
Lamers, H. J. G. L. M.; Cassatella, A.; Korevaar, P.
Radial velocity variations of six Fe II and six Fe III lines in the UV spectrum of the hypergiant star P Cygni (HD 193237) are studied in 33 high resolution IUE spectra, obtained over an interval of more than 5 yr. The Fe II lines have a stable component at -206±2 km s-1 which did not vary in velocity nor in strength in 5 yr. There are …
A study of ultraviolet spectra of zeta Aurigae/VV Cephei systems. VII. Chromospheric density distribution and wind acceleration region.
Schroeder, K. -P.
Chromospheric eclipse spectra have been obtained for three Zeta Aurigae binary systems using the International Ultraviolet Explorer (IUE) spacecraft. In order to fit average density models to the chromospheres, 3 samples of column densities (for 31 Cygni, 32 Cygni, and Zeta Aurigae K giants) were used. Wind velocities were derived assuming a conti…
The explanation of the 1400 and 1600 A features in DA white dwarfs.
Koester, D.; Weidemann, V.; Vauclair, G. +1 more
The authors present new IUE observations of 4 cool DA white dwarfs together with additional data for 8 objects from the literature. All objects show absorption features near 1400 and/or 1600 Å, which were already noted by other authors. These features are explained as due to quasi-molecular absorption of the H2 (1600 Å) resp. H2
Peculiar motions and star formation in the interacting galaxy complexMK 171 = NGC 3690+IC 694.
Lequeux, J.; Augarde, R.
Spectroscopic observations in the visible and in the far ultraviolet are combined with other existing information to interpret the properties of the exceptionally active extended star formation in Mk 171. The authors show that this system corresponds to the interaction, and probably to the direct collision, of two galaxies with a total mass of ⪉4×…
The continuum variability of the puzzling X-ray three-period cataclysmic variable 2A 0526-328 (TV Col).
Motch, C.; Bonnet-Bidaud, J. M.; Mouchet, M.
TV Col is characterized on the basis of 120-195-nm and 190-320-nm large-aperture low-dispersion IUE spectra obtained between April 1980 and May 1982, UBV measurements obtained with the 1-m telescope at ESO in November 1979 (Motch, 1981), and JHK photometry obtained using the standard IR photometer on the 3.6-m telescope at ESO on Dec. 31, 1982. Th…
The International Ultraviolet Explorer (IUE) point spread function at low resolution.
Cassatella, A.; Barbero, J.; Benevenuti, P.
The resolution performances obtainable with IUE low resolution images are reviewed. It is shown that the spatial resolution (perpendicular to the dispersion) is strongly dependent on the telescope focussing conditions while the spectral resolution is not. After determining the telescope optimum focussing conditions, information is provided on the …