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arXiv · 1706.05051

KIC 8164262: a Heartbeat Star Showing Tidally Induced Pulsations with Resonant Locking

K. Hambleton·J. Fuller·S. Thompson·A. Prša·D. W. Kurtz·A. Shporer·H. Isaacson·A. W. Howard·M. Endl·W. Cochran·S. J. Murphy
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Abstract

We present the analysis of KIC 8164262, a heartbeat star with a high-amplitude (~1 mmag), tidally resonant pulsation (a mode in resonance with the orbit) at 229 times the orbital frequency and a plethora of tidally induced g-mode pulsations (modes excited by the orbit). The analysis combines Kepler light curves with follow-up spectroscopic data from the Keck telescope, KPNO (Kitt Peak National Observatory) 4-m Mayal telescope and the 2.7-m telescope at the McDonald observatory. We apply the binary modelling software, PHOEBE, to the Kepler light curve and radial velocity data to determine a detailed binary star model that includes the prominent pulsation and Doppler boosting, alongside the usual attributes of a binary star model (including tidal distortion and reflection). The results show that the system contains a slightly evolved F star with an M secondary companion in a highly eccentric orbit (e = 0.886). We use the results of the binary star model in a companion paper (Fuller et al., 2017) where we show that the prominent pulsation can be explained by a tidally excited oscillation mode held near resonance by a resonance locking mechanism.

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K. Hambleton, J. Fuller, S. Thompson, A. Prša, D. W. Kurtz, A. Shporer, H. Isaacson, A. W. Howard, M. Endl, W. Cochran, S. J. Murphy. 2017-06-15. KIC 8164262: a Heartbeat Star Showing Tidally Induced Pulsations with Resonant Locking. https://doi.org/10.1093/mnras%2Fstx2673

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