749 datasets found

We analyze the non-standard mixing history of the solar twins HIP 55459, HIP 79672, HIP 56948, HIP 73815, and HIP 100963, to determine as precisely as possible their mass and...

The massive Arches cluster near the Galactic center should be an ideal laboratory for investigating massive star formation under extreme conditions. But it comes at a high...

The SDSS Data Release 1 includes 1833 DA white dwarfs (WDs) and forms the largest homogeneous sample of WDs. This sample provides the best opportunity to study the statistical...

To simulate the population of the primordial blue stragglers in old open clusters, a grid of close binaries experiencing mass exchange is needed. To this aim, various...

Coordinates and photometry of very low mass objects near epsilon Ori are presented. The RIJHK photometry of these objects is consistent with membership of the young Ori OB Ib...

We present the catalogue of 112 massive isolated white dwarfs, both magnetic and nonmagnetic, with masses M>0.8M_{sun}_. Mass determinations and other parameters of white...

We investigate the sample of 1175 new nonmagnetic DA white dwarfs with the effective temperatures T_eff_>=12000K, which were extracted from the Data Release 1 of the Sloan...

Coordinates and photometry of probable cluster members in the sigma Ori cluster. Time series observations of this cluster were carried out using the CCD cameras at the 2m...

We present stellar parameters and metallicities, obtained from a detailed spectroscopic analysis, for a large sample of 98 stars known to be orbited by planetary mass companions...

We have reconstructed the galactic orbits of the parent stars of exoplanets. For comparison, we have recalculated the galactic orbits of stars from the Edvardsson et al. (1993,...

File table2 contains the values of the color indices: (b-y), m1, c1, H{beta}, from the Stroemgren photometry and the observational errors on these indices as given by the Hauck...

We have started a large survey for radial velocity variations in white dwarfs (PI R. Napiwotzki) with the aim of finding close double degenerates, which could be precursor...

We derive stellar ages, from evolutionary tracks, and metallicities, from Stroemgren photometry, for a sample of 5828 dwarf and sub-dwarf stars from the Hipparcos (Cat. )...

The Hipparcos mission has made it possible to constrain the positions of nearby field stars in the colour-magnitude diagram with very high accuracy. These positions can be...

The paper gives orbits and masses for some 200 nearby visual binaries, as derived from combining ground-based and Hipparcos data. Table 6 gives identifications and notes, and...

Physical properties and absolute magnitudes of low-mass stars for different initial metallicity [M/H], helium mass fraction Y and mixing length parameter Lmix: mass (in solar...

On the basis of the best available member list and duplicity information, we have studied the radial structure of Praesepe and of the very young open cluster NGC 6231. We have...

New ages are computed for the stars from the Edvardsson et al. (1993, Cat. ) data set. The revised values are systematically larger toward older ages (t>4Gyr), while they are...

On the basis of the best available member list and duplicity information, we have studied the radial distribution of 270 stars and multiple systems earlier than K0 in the...

Properties of Very Low mass stars for different initial metallicity [M/H] and Helium mass fraction: mass (in solar mass), age (in Gyrs) effective temperature (in K), log of...