Search Publications
The Tycho double star catalogue
Makarov, V. V.; Fabricius, C.; Urban, S. E. +3 more
We report the discovery of 13 251 visual double stars, mostly with separations between 0.3 and 1 arcsec, from a dedicated re-reduction of the Tycho data from the star mapper of the ESA Hipparcos satellite. The new doubles are combined with 18 160 WDS systems identified in the Tycho-2two, and 1220 new Tycho-2 doubles, to form the Tycho Double Star …
Speckle interferometry of nearby multiple stars
Weigelt, G.; Hofmann, K. -H.; Schertl, D. +5 more
We present the results of diffraction-limited optical speckle interferometry and infrared bispectrum speckle interferometry of 111 double and 10 triple systems performed in 1998-1999 with the 6-m telescope of the Special Astrophysical Observatory in Zelenchuk. The observations concentrated on nearby close binaries discovered during the Hipparcos m…
Astrometric radial velocities. III. Hipparcos measurements of nearby star clusters and associations
Lindegren, Lennart; Madsen, Søren; Dravins, Dainis
Radial motions of stars in nearby moving clusters are determined from accurate proper motions and trigonometric parallaxes, without any use of spectroscopy. Assuming that cluster members share the same velocity vector (apart from a random dispersion), we apply a maximum-likelihood method on astrometric data from Hipparcos to compute radial and spa…
A study of bright southern slowly pulsating B stars. II. The intrinsic frequencies
Aerts, C.; De Cat, P.
We present the results of detailed frequency analyses of a sample of thirteen confirmed slowly pulsating B stars. Our analysis is based on a combination of elaborate photometric and spectroscopic data-sets. The original sample consists of a mixture of five confirmed slowly pulsating B stars and twelve candidate slowly pulsating B stars discovered …
Rotational velocities of A-type stars. I. Measurement of v sin i in the southern hemisphere
Royer, F.; Gerbaldi, M.; Faraggiana, R. +1 more
Within the scope of a Key Programme determining fundamental parameters of stars observed by HIPPARCOS, spectra of 525 B8 to F2-type stars brighter than V=8 have been collected at ESO. Fourier transforms of several line profiles in the range 4200-4500 Å are used to derive v sin i from the frequency of the first zero. Statistical analysis of the sam…
A multi-epoch spectrophotometric atlas of symbiotic stars
Munari, U.; Zwitter, T.
A multi-epoch, absolute-fluxed spectral atlas extending from about 3200 to 9000 Å is presented for 130 symbiotic stars, including members of the LMC, SMC and Draco dwarf galaxies. The fluxes are accurate to better than 5% as shown by comparison with Tycho and ground-based photometric data. The spectra of 40 reference objects (MKK cool giant standa…
Multiplicity among chemically peculiar stars. II. Cool magnetic Ap stars
Babel, J.; Carrier, F.; Udry, S. +1 more
We present new orbits for sixteen Ap spectroscopic binaries, four of which might in fact be Am stars, and give their orbital elements. Four of them are SB2 systems: HD 5550, HD 22128, HD 56495 and HD 98088. The twelve other stars are: HD 9996, HD 12288, HD 40711, HD 54908, HD 65339, HD 73709, HD 105680, HD 138426, HD 184471, HD 188854, HD 200405 a…
On Be star candidates and possible blue pre-main sequence objects in the Small Magellanic Cloud
Mennickent, R. E.; Gieren, W.; Pietrzyński, G. +1 more
Recently the OGLE experiment has provided accurate light curves and colours for about 2 millions stars in the Small Magellanic Cloud. We have examined this database for its content of Be stars, applying some selection criteria, and we have found a sample of ~ 1000 candidates. Some of these stars show beautiful light curves with amazing variations …
The origin of the young stellar population in the solar neighborhood -- A link to the formation of the Local Bubble?
Breitschwerdt, D.; Berghöfer, T. W.
We have analyzed the trajectories of moving stellar groups in the solar neighborhood in an attempt to estimate the number of supernova explosions in our local environment during the past 20 million years. Using Hipparcos stellar distances and the results of kinematical analyses by Asiain et al. (\cite{Asiain1999a}a) on the Pleiades moving groups, …
HIPPARCOS age-metallicity relation of the solar neighbourhood disc stars
Arimoto, N.; Ibukiyama, A.
We derive age-metallicity relations (AMRs) and orbital parameters for the 1658 solar neighbourhood stars to which accurate distances are measured by the HIPPARCOS satellite. The sample stars comprise 1382 thin disc stars, 229 thick disc stars, and 47 halo stars according to their orbital parameters. We find a considerable scatter for thin disc AMR…