* Astronomy

Title: KIC 10080943: An eccentric binary system containing two pressure and gravity mode hybrid pulsators
Author: V. S. Schmid, A. Tkachenko, C. Aerts, P. Degroote, S. Bloemen, S. J. Murphy, T. Van Reeth, P. I. Papics, T. R. Bedding, M. A. Keen, A. Prsa, J. Menu, J. Debosscher, M. Hrudkova, K. De Smedt, R. Lombaert, P. Nemeth

Gamma Doradus and delta Scuti pulsators cover the transition region between low mass and massive main-sequence stars, and are as such critical for testing stellar models. When they reside in binary systems, we can combine two independent methods to derive critical information, such as precise fundamental parameters to aid asteroseismic modelling. In the Kepler light curve of KIC10080943, clear signatures of gravity and pressure mode pulsations have been found. Ground-based spectroscopy revealed this target to be a double-lined binary system. We present the analysis of four years of Kepler photometry and high-resolution spectroscopy to derive observational constraints, which will serve to evaluate theoretical predictions of the stellar structure and evolution for intermediate-mass stars. We used the method of spectral disentangling to determine atmospheric parameters for both components and derive the orbital elements. With phoebe we modelled the ellipsoidal variation and reflection signal of the binary in the light curve and used classical Fourier techniques to analyse the pulsation modes. We show that the eccentric binary system KIC10080943 contains two hybrid pulsators with masses M_1=2.0±0.1 solar masses and M_2=1.9±0.1 solar masses, with radii R_1=2.9±0.1 solar radii and R_2=2.1±0.2 solar radii. We detect rotational splitting in the g modes and p modes for both stars and use them to determine a first rough estimate of the core-to-surface rotation rates for the two components, to be improved by future detailed seismic modelling.

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