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arXiv · 2606.26817

Investigating the System Configuration of Kepler-451 through Orbital Period Variations: Dynamical and Magnetic Interpretations

Huseyin Er·Aykut Ozdonmez·M. Emir Kenger·B. Batuhan Gurbulak·Ilham Nasiroglu·Murat Tekkesinoglu·Ergun Ege·Nazli Karaman
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Abstract

We present an analysis of eclipse timing variations in Kepler-451 using data spanning 2004-2024 from both ground- and space-based observations. Using two datasets, DS-A and DS-B, we constructed updated O-C diagrams. By modeling both datasets with various LTT configurations, we tested for the presence of circumbinary companions. For DS-A, the two-companion model (LTT34) provides the best fit with RMS = 3.23 s and chi^2_nu = 1.23, while inclusion a fifth body (LTT345) does not improve the fit (RMS = 3.24 s, chi^2_nu = 1.28). For DS-B, the three-companion model (LTT345) yields the best fit (RMS = 2.31 s, chi^2_nu = 1.01), although the semi-amplitude of the inner companion (1.34 s) is smaller than the systematic error (1.81 s), suggesting that it may originate from observational or calibration systematics. Applegate-mechanism tests indicate that most signals exceed the available energy budget, while the outer LTT terms in both datasets remain consistent with the Standard model and may have a magnetic origin. Removing these magnetic terms yields dynamically stable configurations for at least 10^7 yr. These findings support the presence of a second-generation circumbinary planet at 3.4 AU around Kepler-451, while the origin of the remaining LTT signals remains uncertain.

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Huseyin Er, Aykut Ozdonmez, M. Emir Kenger, B. Batuhan Gurbulak, Ilham Nasiroglu, Murat Tekkesinoglu, Ergun Ege, Nazli Karaman. 2026-06-25. Investigating the System Configuration of Kepler-451 through Orbital Period Variations: Dynamical and Magnetic Interpretations. https://doi.org/10.3847/1538-4357%2Fae1029

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