A highly mutually inclined compact warm-Jupiter system KOI-984?. Issue 3 (8th April 2022)

• Record Type: Journal Article
• Authors: Sun, L; Ioannidis, P; Gu, S; Schmitt, J H M M; Wang, X; Kouwenhoven, M B N; Perdelwitz, V; Flammini Dotti, F; Czesla, S
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 512:Issue 3(2022)
• Page Start: 4604
• Page End: 4617
• Publication Date: 2022-04-08
• Subjects: techniques: photometric -- planets and satellites: detection -- star: individual (KOI-984); Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stab3367
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: The discovery of a population of close-orbiting giant planets (≤ 1 au) has raised a number of questions about their origins and dynamical histories. These issues have still not been fully resolved, despite over 20 years of exoplanet detections and a large number of discovered exoplanets. In particular, it is unclear whether warm Jupiters (WJs) form in situ, or whether they migrate from further outside and are even currently migrating to form hot Jupiters. Here, we report the possible discovery and characterization of the planets in a highly mutually inclined ( I mut ≃ 45°) compact two-planet system (KOI-984), in which the newly discovered warm Jupiter KOI-984 c is on a 21.5-d moderately eccentric ( e ≃ 0.4) orbit, in addition to a previously known 4.3-d planet candidate KOI-984 b . Meanwhile, the orbital configuration of a moderately inclined ( I mut ≃ 15°) low-mass ( mc ≃ 24M⊕ ; Pb ≃ 8.6 d) perturbing planet near the 1:2 mean-motion resonance with KOI-984 b could also well reproduce the observed transit-timing variations and transit-duration variations of KOI-984 b . Such an eccentric WJ with a close-in sibling would pose a challenge to the proposed formation and migration mechanisms of WJs if the first scenario is supported with more evidence in the near future; this system with several other well measured inclined WJ systems (e.g. Kepler-419 and Kepler-108) may provide additional clues to the origin and dynamical histories of WJs.