000003454 001__ 3454
000003454 005__ 20180126125004.0
000003454 037__ $$aSCART-2018-0031
000003454 088__ $$aarXiv:1711.11265
000003454 100__ $$aSamadi Gh., A.
000003454 245__ $$aKIC 6048106: An Algol-type Eclipsing System with Long-term Magnetic Activity and Hybrid Pulsations. I. Binary Modelling
000003454 260__ $$c2018
000003454 520__ $$aThe A-F-type stars and pulsators (δ Scuti-γ Dor) are in a critical regime where they experience a transition from radiative to convective transport of energy in their envelopes. Such stars can pulsate in both gravity and acoustic modes. Hence, the knowledge of their fundamental parameters along with their observed pulsation characteristics can help in improving the stellar models. When residing in a binary system, these pulsators provide more accurate and less model-dependent stellar parameters than in the case of their single counterparts. We present a light-curve model for the eclipsing system KIC 6048106 based on the Kepler photometry and the code PHOEBE. We aim to obtain accurate physical parameters and tough constraints for the stellar modelling of this intermediate-mass hybrid pulsator. We performed a separate modelling of three light-curve segments which show a distinct behaviour due to a difference in activity. We also analysed the Kepler Eclipse Time Variations (ETVs). KIC 6048106 is an Algol-type binary with F5-K5 components, a near-circular orbit and a 1.56-d period undergoing variations of the order of Δ P/P˜eq 3.60× 10^{-7} in 287 ± 7 d. The primary component is a main-sequence star with M1 = 1.55 ± 0.11 M⊙, R1 = 1.57 ± 0.12 R⊙. The secondary is a much cooler subgiant with M2 = 0.33 ± 0.07 M⊙, R2 = 1.77 ± 0.16 R⊙. Many small near-polar spots are active on its surface. The second quadrature phase shows a brightness modulation on a time-scale 290 ± 7 d, in good agreement with the ETV modulation. This study reveals a stable binary configuration along with clear evidence of a long-term activity of the secondary star. 
000003454 594__ $$aNO
000003454 6531_ $$atechniques: photometric
000003454 6531_ $$abinaries: eclipsing
000003454 6531_ $$astars: fundamental parameters
000003454 6531_ $$astars: oscillations
000003454 6531_ $$astarspots
000003454 6531_ $$astars: variables: δ Scuti
000003454 700__ $$aLampens, P.
000003454 700__ $$aJassur, D. M.
000003454 773__ $$c5549$$pMNRAS$$v474$$y2018
000003454 8560_ $$fpatricia.lampens@observatoire.be
000003454 905__ $$apublished in
000003454 980__ $$aREFERD