Analysis of delta Librae including Hipparcos astrometry
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, cilt.370, sa.4, ss.1935-1945, 2006 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 370 Sayı: 4
- Basım Tarihi: 2006
- Doi Numarası: 10.1111/j.1365-2966.2006.10619.x
- Dergi Adı: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.1935-1945
- Anahtar Kelimeler: binaries : close, stars : individual : delta Lib, ECLIPSING BINARIES, ALGOL SYSTEM, STARS, PHOTOMETRY, EVOLUTION, VELOCITY, CURVES
- Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
- Akdeniz Üniversitesi Adresli: Hayır
Özet
New spectroscopy of the classical Algol system delta Lib, combined with high-quality optical and infrared photometry, provides the basis for a good understanding of the close binary system's main parameters. Detailed analysis of the photometry reveals the significant role of a third light source, pointing to the existence of a companion to the eclipsing system of mass similar to 1 M-circle dot.
We review the methodology of applying high-accuracy positional information, available from the Hipparcos Intermediate Astrometric Data archive, to stars that may have such companions. Analysis of the astrometry of delta Lib also points to a third star similar to the one already identified by Worek from radial-velocity data, although with slightly revised parameters. O-C data do not contradict this, but their general precision (while confirming the close pair's Algol status) fails to allow a decision on the third orbit parameters: Worek's or revised ones. Taking the photometry, spectroscopy and astrometry together, however, the existence of a third star of comparable mass to the Sun, as a relatively close companion to the eclipsing binary (similar to 4 au), is confirmed.