Orbit evolution of the binary system 9 Cyg
Abstract:The composite spectrum star 9 Cyg is known as a spectroscopic and interferometric binary with an orbit period of 4.3 years. Speckle interferometric observations of the system were performed at the 6 m BTA telescope, while the spectra in the 3700-9200 A band were obtained with the 2 m telescope at Peak Terskol. A detailed analysis of the atmosphere of the system's main component was carried out using the collected data. An evolutionary status of 9 Cyg can be established from the collected data. The age of the system is approximately 400 million years, the brighter star being at the red giants transition stage, while the secondary is still passing the hydrogen burning stage close to the zero-age main sequence. A model is proposed of the orbit evolution, which explains its high eccentricity, e=0.79.
Document Type: Research Article
Publication date: February 1, 2007