Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars: The Triple System V1061 Cygni

Details Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars: The Triple System V1061 Cygni Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars: The Triple System V1061 Cygni

Aug 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007iaus..240..658t&link_type=abstract

Binary Stars as Critical Tools & Tests in Contemporary Astrophysics, Proceedings of IAU Symposium #240, held 22-25 August, 2

Astronomy and Astrophysics

Astrophysics

Scientific paper

We present spectroscopic and photometric observations of the chromospherically active (X-ray strong) eclipsing binary V1061 Cyg (P = 2.35 days) showing that it is in reality a hierarchical triple system. We combine these observations with Hipparcos intermediate data (abscissa residuals) to derive the outer orbit with a period of 15.8 yr. We determine accurate values for the masses, radii, and effective temperatures of the eclipsing binary components, as well as for the mass and temperature of the third star. For the primary we obtain M = 1.282 0.017 R, Teff = 6180 0.0068 M, R = 0.974 150 K, and for the tertiary M = 0.925 100 K. Current stellar evolution models agree well with the properties of the primary star, but show a large discrepancy in the radius of the secondary in the sense that the observed value is about 10% larger than predicted (a 5σ effect). We also find the secondary temperature to be 200 K cooler than indicated by the models. These discrepancies are quite remarkable considering that the secondary is only 7% less massive than the Sun, which is the calibration point of all stellar models. Similar differences with theory have been seen before for lower mass stars. We identify chromospheric activity as the likely cause of the effect. Inactive stars agree very well with the models, while active ones such as the secondary of V1061 Cyg appear systematically too large and too cool. Both of these differences are understood in terms of the effects of magnetic fields commonly associated with chromospheric activity.

Affiliated with

Also associated with

No associations

Rating

Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars: The Triple System V1061 Cygni 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 Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars: The Triple System V1061 Cygni, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Confronting Stellar Evolution Models for Active and Inactive Solar-Type Stars: The Triple System V1061 Cygni will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1811274