The eccentric massive binary V380 Cyg: revised orbital elements and interpretation of the intrinsic variability of the primary component*

Tkachenko, A.; Degroote, P.; Aerts, C.; Pavlovski, K.; Southworth, J.; Pápics, P. I.; Moravveji, E.; Kolbas, V.; Tsymbal, V.; Debosscher, J.; Clémer, K.

Abstract

We present a detailed analysis and interpretation of the high-mass binary V380 Cyg, based on high-precision space photometry gathered with the Kepler space mission as well as high-resolution ground-based spectroscopy obtained with the HERMES spectrograph attached to the 1.2 m Mercator telescope. We derive a precise orbital solution and the full physical properties of the system, including dynamical component mass estimates of 11.43 ± 0.19 and 7.00 ± 0.14 M⊙ for the primary and secondary, respectively. Our frequency analysis reveals the rotation frequency of the primary in both the photometric and spectroscopic data and additional low-amplitude stochastic variability at low frequency in the space photometry with characteristics that are compatible with recent theoretical predictions for gravity-mode oscillations excited either by the convective core or by sub-surface convective layers. Doppler imaging analysis of the silicon lines of the primary suggests the presence of two high-contrast stellar surface abundance spots which are located either at the same latitude or longitude. Comparison of the observed properties of the binary with present-day single-star evolutionary models shows that the latter are inadequate and lack a serious amount of near-core mixing.

Citation

Tkachenko, A., Degroote, P., Aerts, C., Pavlovski, K., Southworth, J., Pápics, P. I., …Clémer, K. (2014). The eccentric massive binary V380 Cyg: revised orbital elements and interpretation of the intrinsic variability of the primary component*. Monthly Notices of the Royal Astronomical Society, 438(4), 3093-3110. https://doi.org/10.1093/mnras/stt2421

• Journal Article Type: Article
• Acceptance Date: Dec 12, 2013
• Online Publication Date: Jan 14, 2014
• Publication Date: Mar 11, 2014
• Deposit Date: Jun 16, 2023
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 0035-8711
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 438
• Issue: 4
• Pages: 3093-3110
• DOI: https://doi.org/10.1093/mnras/stt2421
• Keywords: Space and Planetary Science; Astronomy and Astrophysics; binaries: eclipsing, stars: fundamental parameters, stars: individual: V380 Cyg, stars: oscillations, stars: variables: general