Search Publications
Statistics of Hipparcos binaries: probing the 1-10 AU separation range
Lindegren, L.; Quist, C. F.
The observation of double stars by Hipparcos is modelled in order to check the statistics of double-star solutions in the Hipparcos Catalogue and to set quantitative limits on binary distributions. A Galaxy model is combined with models of binary distributions and of the observation process to derive the expected numbers of the different kinds of …
New astrometric binaries among HIPPARCOS stars
Gontcharov, G. A.; Andronova, A. A.; Titov, O. A.
A new realization of the International Celestial Reference System (ICRS) is built upon the data of the HIPPARCOS catalogue and astrometric ground-based catalogues of the 20th century reduced to the HIPPARCOS system. Non-linear motion of some stars has been detected with this realization of the ICRS. This motion is separated into the pro…
Search for an exosphere around 51 Pegasi B with ISO
Rauer, H.; Schneider, J.; Bockelée-Morvan, D. +2 more
The detection of absorption features in spectra of 51 Peg obtained during transit of its planet would provide a first clue on the physical nature of the planet. We have searched for signatures of an exosphere of the planet orbiting 51 Peg in the wavelength range from 2.39 µm to 3.5 µm and from 4.55 µm to 4.74 µm using SWS o…
Physical properties of the pulsating hydrogen-deficient star LSS 3184 (BX Cir )
Jeffery, C. S.; Woolf, V. M.
We report new determinations of the radius and mass of the pulsating helium-rich, hydrogen-deficient star
Comparative abundance analysis of the hot main sequence stars and their progeny in open cluster M 25
Korotin, S. A.; Andrievsky, S. M.; Kovtyukh, V. V. +2 more
Remarkable inconsistencies between elemental abundances in the main sequence stars and their progeny F-G supergiants are discussed. Comparative abundance analysis of the hot main sequence stars, the cepheid U Sgr and two cool supergiants belonging to young open cluster M 25 is performed. The detected disaccord in the abundances of carbon, oxygen a…
Lensing properties of 7 damped Lyalpha absorbing galaxy-QSO pairs
Surdej, J.; Smette, A.; Le Brun, V. +1 more
Le Brun et al. (1997) presented the first identifications of the galaxies giving rise to 7 intermediate redshift damped Lyalpha (DLA) absorption systems. Here, we study the gravitational lensing properties of these foreground galaxies based on their observed optical appearance and on the absence of any secondary lensed quasar image. We consider th…
Eclipse mapping of the accretion stream in UZ Fornacis
Gänsicke, B. T.; Beuermann, K.; Kube, J.
We present a new method to map the surface brightness of the accretion streams in
Photometric and spectroscopic studies of cool stars discovered in EXOSAT X-ray images. IV. The northern hemisphere sample
Tagliaferri, G.; de Medeiros, J. R.; Messina, S. +4 more
We present high-precision photometry, high- and medium-resolution spectroscopy for a sample of 32 stars likely to be the optical counterparts of X-ray sources serendipitously detected by the EXOSAT satellite. Using also recent results from the Hipparcos satellite, we infer spectral types, compute X-ray luminosities and Li abundances and investigat…
The protostellar system HH108MMS
Siebenmorgen, R.; Krügel, E.
We probe the region around the protostar HH108MMS by deep mid infrared photometric and polarimetric imaging. The protostar is detected at 14mu m in absorption against the diffuse background. Next to HH108MMS, we find a second absorbing core, named Q1, and the young stellar object IRAS18331-0035 which is more advanced in its evolution and already s…
The active binary star II Pegasi with it BeppoSAX
Covino, S.; Tagliaferri, G.; Mewe, R. +2 more