Search Publications
IR survey of OB emission-line stars in the SMC : detection of a new B E supergiant, AV 172.
Stahl, O.; Zickgraf, F. -J.; Wolf, B.
We surveyed bright SMC emission-line stars in the infrared (JHK) in order to search for more B[e] supergiants in this galaxy by means of their IR excesses. One new star, AV 172, with the B [e] type IR excess was detected. Optical and IUE spectroscopy of this star showed it to be a B8 [e]Ib supergiant. Our survey showed that in the SMC four B [e] s…
Positions and parallaxes from the HIPPARCOS satellite - A first attempt at a global astrometric solution
Lindegren, L.; van Leeuwen, F.; Perryman, M. A. C. +2 more
The last stage of the basic astrometric reduction of Hipparcos data is to combine angular measurements along great-circle scans into a globally coherent system of positions, proper motions and trigonometric parallaxes. We report the results of a first attempt at such a 'sphere solution' of positions and parallaxes using great-circle results calcul…
CPC2 - the Second Cape Photographic Catalog - Part Two - Conventional Plate Adjustment and Catalog Construction
Zacharias, N.; de Vegt, C.; Nicholson, W. +1 more
The Second Cape Photographic Catalog CPC 2, containing positions and visual magnitudes of 276 t 31 stars in the approximate magnitude range V= 6.5-10.5 is the first modern photographic catalog project on the southern hemisphere with an optimal fourfold plate overlap pattern and an astrometrically optimized spectral bandpass in the yellow - red reg…
HEXE observations of active galactic nuclei : constraints on pairs and Compton reflection.
Pietsch, W.; Sunyaev, R.; Kendziorra, E. +10 more
We present results of X-ray observations of the three brightest Active Galaxies in hard X-rays, the quasar 3C 273 (1226+02), the Seyfert galaxy NGC 4151, and the radio galaxy Cen A (NGC 5128). The observations were made with the HEXE instrument (20-200 keV) on board the Mir space station. We discuss the spectra of the sources in the context of mod…
The HIPPARCOS Input Catalogue. III - Photometry
Grenon, M.; Mermilliod, J. C.; Mermilliod, M.
Photometric information about stars proposed for observation by the astrometric satellite Hipparcos is used for several purposes. Instrumental colors and magnitudes served as an input to the definition of the observing program (e.g. in defining the magnitude-limited survey), in optimizing the observations by allocating observing time according to …
Detection and measurement of double stars with the HIPPARCOS satellite - NDAC reductions
Evans, D. W.; Lindegren, L.; van Leeuwen, F. +1 more
The Hipparcos satellite has a predefined observing program given by an Input Catalogue with 118,000 entries. This includes about 10,000 members of known double or multiple systems (with separations above 0.1 arcsec and magnitude differences below 4-5), which will be observably non-single and thus need a more complex reduction procedure. Also, a si…
The 1990 outburst of the recurrent nova V3890 Sgr observed with IUE.
Gonzalez-Riestra, R.
V3890 Sgr (Nova Sgr 1962) is one of the more recent examples of recurrent novae. Its second recorded outbursts took place in April 1990. IUE observations were obtained during the first month after the outburst. The UV spectra show the development of very broad emission lines with complex and variable profiles. Of particular interest is the "narrow…
HIPPARCOS double star recognition and processing within the FAST consortium
Badiali, M.; Cardini, D.; Emanuele, A. +4 more
The Hipparcos observations are potentially a source of discovery of new systems of double and multiple stars. Procedures have been developed to recognize in the signal parameters the multiplicity of the stellar objects. The principles applied to the recognition of double stars are presented in this paper along with statistical tests. Results based…
A two-wind radiation-driven model for the atmospheric features of beta Lyrae.
Pauldrach, A. W. A.; Puls, J.; Mazzali, P. A. +1 more
The properties of the non-degenerate interacting binary system of β Lyrae (B6.5 II p+BO V) are investigated via the analysis of its mass loss features.
As a first step, it is shown that the UV emission lines, observed in high dispersion by lUE, can be divided into two groups: one including the `superionised' hot-star wind resonance lines (N V…Optical spectra of dzeta Aurigae systems. IV. The January 1990 eclipse ofHR 2554 : detection of chomospheric absorption and extended plasma at 10 5 K.
Schroeder, K. -P.; Huensch, M.
Eclipse observations of HR 2554 are presented. These observations were obtained simultaneously during the January 1990 eclipse with ESO telescopes and the IUE satellite. Chromospheric absorption and changes in the circumstellar matter were investigated. Improved system parameters were derived from the light curve. For each of the composite spectra…