Astronomy and Astrophysics – Astrophysics
Scientific paper
Aug 2007
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007iaus..240..265g&link_type=abstract
Binary Stars as Critical Tools and Tests in Contemporary Astrophysics, International Astronomical Union. Symposium no. 240, he
Astronomy and Astrophysics
Astrophysics
Scientific paper
Stellar pairs with large magnitude difference and period of several decades are hard to investigate by spectroscopic, interferometric and visual methods. A combination of Hipparcos and ground-based astrometry (see Gontcharov and Kiyaeva, 2002A&A...391..647G) can help to derive orbits and masses for such astrometric binaries. A direct combination of the Hipparcos/Tycho data with 400 astrometric ground-based catalogues of the 20th century (including all ground-based catalogues used for Tycho-2) reduced to the ICRF/Hipparcos system is used to detect the variations of transversal velocity with median precision of 1 mas/year which corresponds to 0.5 km/s at 100 pc. The radial velocity variations are detected with median precision of 0.7 km/s as a by-product of a new compilation of 500 sources of precise radial velocities (including WEB, Barbier-Brossat and Figon, Geneva-Copenhagen survey (2004A&A...418..989N) and CORAVEL K-M giants (2005A&A...430..165F)) reduced to a common new standard of 837 stars, the Pulkovo RAdial VELOcities catalogue of 35000 stars (PRAVELO, www.geocities.com/orionspiral). Similar precision allows us to use transversal and radial velocities together. However, the data are still rather heterogeneous and have small S/N ratio mainly because the accuracy of observations improved with time. Therefore, least square solution uncertainties show several minima. A new approach is developed to solve it. As the first result, the preliminary orbits and component masses are calculated for 100 astrometric binaries with no previous orbit calculation and 20 binaries with known visual or spectroscopic orbit. Many new orbital pairs appear to be A, F, G stars with white dwarfs. The duplicity/multiplicity of many famous stars is discussed in detail, such as Polaris, Mizar and Arcturus. This research is a part of Orion Spiral Arm CAtalogue project (OSACA) supported by Russian Foundation for basic research grant 05-02-17047.
No associations
LandOfFree
A Hundred New Preliminary Orbits and Masses from Hipparcos, Ground-based Astrometry and Radial Velocities does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Hundred New Preliminary Orbits and Masses from Hipparcos, Ground-based Astrometry and Radial Velocities, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Hundred New Preliminary Orbits and Masses from Hipparcos, Ground-based Astrometry and Radial Velocities will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1811027