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arXiv · 2607.18811

KIC 6464285: A Solar-type Eclipsing Binary in a Hierarchical Triple System with Quasi-periodic Out-of-eclipse Modulations

Fang-Bin Meng·Li-Ying Zhu·Sheng-Bang Qian·Ildar Asfandiyarov·Azizbek Matekov·Jaqsiliq Baltamuratov·Wen-Ping Liao·A-Li Luo·Wen Hou·Ping Li·Lin-Jia Li·Er-Gang Zhao·Jia-Jia He
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Abstract

We present the first detailed analysis of the solar-type triple system KIC 6464285. Combining long-term, high-precision photometry from Kepler, TESS, and ZTF with low-resolution spectra from LAMOST and near-infrared high-resolution spectra from SDSS/APOGEE, we performed a joint analysis of the light curves, eclipse timing variations (ETVs), and radial velocities. Spectroscopic analysis reveals the system to be triple-lined, with the inner binary's primary being a G-type main-sequence star and a mass ratio of $0.627(7)$. Light curve modeling indicates that the inner binary is detached, with filling factors of approximately 26\% and 11\% for the primary and secondary, respectively, and a tertiary light contribution of about 27\%. ETV analysis shows a significant light-travel-time effect (LTTE), consistent with the presence of the tertiary companion, whose minimum mass is estimated as $M_{3,\rm min}=0.74(1)~M_\odot$. The light curve exhibits a pronounced O'Connell effect and quasi-periodic variations, indicative of starspot activity modulating the photometry on a $\sim$131-day timescale. Kepler observations further reveal 30 superflares, each with total energies exceeding $10^{34}$ erg. This study presents detailed observational constraints on the orbital configuration, stellar properties, and magnetic activity of KIC 6464285, providing a benchmark for studies of hierarchical triple systems.

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Fang-Bin Meng, Li-Ying Zhu, Sheng-Bang Qian, Ildar Asfandiyarov, Azizbek Matekov, Jaqsiliq Baltamuratov, Wen-Ping Liao, A-Li Luo, Wen Hou, Ping Li, Lin-Jia Li, Er-Gang Zhao, Jia-Jia He. 2026-07-21. KIC 6464285: A Solar-type Eclipsing Binary in a Hierarchical Triple System with Quasi-periodic Out-of-eclipse Modulations. https://doi.org/10.3847/1538-4357%2Fae677e

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