KIC 7955301: a hierarchical triple system with eclipse timing variations and an oscillating red giant

Abstract

KIC 7955301 is a hierarchical triple system with eclipse timing and depth variations discovered by the Kepler mission. It is composed of a non-eclipsing primary star at the bottom of the red giant branch on a 209-day orbit with a K/G-type main-sequence inner eclipsing binary, orbiting in 15.3 days. This system was noted for the large amplitude of its eclipse timing variations (4 hours), and the clear solar-like oscillations of the red-giant component, including p-modes of degree up to l=3 and mixed l=1 modes. The system is a single-lined spectroscopic triple. We perform a dynamical model by combining the Kepler photometric data, eclipse timing variations, and radial-velocity data obtained at Apache Point (ARCES) and Haute Provence (SOPHIE) observatories. The dynamical mass of the red-giant is determined with a 2% precision at 1.30 (+0.03,-0.02) solar mass. We perform asteroseismic modeling based on the global seismic parameters and on the individual frequencies. Both methods lead to a mass of the red giant that matches the dynamical mass within the uncertainties. Asteroseismology also reveals the rotation rate of the core (15 days), the envelope (150 days), and the inclination (75 deg) of the red giant. Three different approaches lead to an age between 3.3 and 5.8 Gyr, which highlights the difficulty of determining stellar ages despite the exceptional wealth of available information. On short timescales, the inner binary exhibits eclipses with varying depths during a 7.3-year long interval, and no eclipses during the consecutive 11.9 years. This is why Kepler could detect its eclipses, TESS will not, and the future ESA PLATO mission should. Over the long term, the system owes its evolution to the evolution of its individual components. It could end its current smooth evolution by merging by the end of the red giant or the asymptotic giant branch of the primary star.

arXiv commentAccepted in A&A, 25 pages, 17 figures, 7 tables

References in corpus (82)

• The chemical composition of the Sun
• Gaia Data Release 2. Summary of the contents and survey properties
• Modules for Experiments in Stellar Astrophysics (MESA)
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• MESA Isochrones and Stellar Tracks (MIST). I: Solar-Scaled Models
• Analytic Lightcurves for Planetary Transit Searches
• Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions
• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• The PLATO 2.0 Mission
• Characteristics of planetary candidates observed by Kepler, II: Analysis of the first four months of data
• A Computational Guide to Physics of Eclipsing Binaries. Paper I. Demonstrations and Perspectives
• Kepler Input Catalog: Photometric Calibration and Stellar Classification
• The TESS Input Catalog and Candidate Target List
• GYRE: An open-source stellar oscillation code based on a new Magnus Multiple Shooting Scheme
• Quantifying the Uncertainty in the Orbits of Extrasolar Planets
• Spin down of the core rotation in red giants
• The GALAH Survey: Second Data Release
• The connection between stellar granulation and oscillation as seen by the Kepler mission
• KOI-126: A Triply-Eclipsing Hierarchical Triple with Two Low-Mass Stars
• Periodic Flux Variability of Stars due to the Reflex Doppler Effect Induced by Planetary Companions
• On detecting the large separation in the autocorrelation of stellar oscillation times series
• A Comprehensive Study of the Kepler Triples via Eclipse Timing
• Mixed modes in red giants: a window on stellar evolution
• Testing the asteroseismic scaling relations for Red Giants with Eclipsing Binaries Observed by Kepler
• Age dissection of the Milky Way discs: red giants in the Kepler field
• Period spacings in red giants II. Automated measurement
• The universal red-giant oscillation pattern; an automated determination with CoRoT data
• Observations of Doppler Boosting in Kepler Lightcurves
• Triple-Star Candidates Among the Kepler Binaries
• Radial Velocity Studies of Close Binary Stars.VII. Methods and Uncertainties
• Core rotation braking on the red giant branch for various mass ranges
• FITSH -- a software package for image processing
• Asymptotic and measured large frequency separations
• Pulsating red giant stars in eccentric binary systems discovered from Kepler space-based photometry
• Close Binary Companions to APOGEE DR16 Stars: 20,000 Binary-star Systems Across the Color-Magnitude Diagram
• The Yale-Potsdam Stellar Isochrones (YaPSI)
• Period spacings in red giants I. Disentangling rotation and revealing core structure discontinuities
• HD 181068: A Red Giant in a Triply-Eclipsing Compact Hierarchical Triple System
• Surface rotation of Kepler red giant stars
• Grid Search in Stellar Parameters: a software for spectrum analysis of single stars and binary systems
• Establishing the accuracy of asteroseismic mass and radius estimates of giant stars. I. Three eclipsing systems at [Fe/H]~ -0.3 and the need for a large high-precision sample
• Surface Activity and Oscillation Amplitudes of Red Giants in Eclipsing Binaries
• KIC 8410637: a 408-day period eclipsing binary containing a pulsating red giant
• Discovery of a red giant with solar-like oscillations in an eclipsing binary system from Kepler space-based photometry
• Red Giants in Eclipsing Binary and Multiple-Star Systems: Modeling and Asteroseismic Analysis of 70 Candidates from Kepler Data
• Transit timing variations in eccentric hierarchical triple exoplanetary systems. I. Perturbations on the time-scale of the orbital period of the perturber
• Period spacings in red giants IV: Toward a complete description of the mixed-mode pattern
• Rapid Rotation of Low-Mass Red Giants Using APOKASC: A Measure of Interaction Rates on the Post-main-sequence
• Abundances from disentangled component spectra: the eclipsing binary V578 Mon
• Oscillating red giants in eclipsing binary systems: empirical reference value for asteroseismic scaling relation
• A 20-Second Cadence View of Solar-Type Stars and Their Planets with TESS: Asteroseismology of Solar Analogs and a Re-characterization of pi Men c
• Study of KIC 8561221 observed by Kepler: an early red giant showing depressed dipolar modes
• Systematic search for stellar pulsators in the eclipsing binaries observed by Kepler
• The TESS light curve of AI Phoenicis
• New light on the Gaia DR2 parallax zero-point: influence of the asteroseismic approach, in and beyond the Kepler field
• Period spacings in red giants; III. Coupling factors of mixed modes
• Chemical evolution of high-mass stars in close binaries. II. The evolved component of the eclipsing binary V380 Cygni
• Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era
• Photodynamical analysis of the triply eclipsing hierarchical triple system EPIC 249432662
• Active red giants: close binaries versus single rapid rotators
• KIC 9246715: The Double Red Giant Eclipsing Binary With Odd Oscillations
• SOPHIE velocimetry of Kepler transit candidates IV. KOI-196b: a non-inflated hot-Jupiter with a high albedo
• TICs 167692429 and 220397947: The first compact hierarchical triple stars discovered with TESS
• Semi-analytic Expressions for the Isolation and Coupling of Mixed Modes
• Spectroscopic and seismic analysis of red giants in eclipsing binaries discovered by Kepler
• Fundamental effective temperature measurements for eclipsing binary stars I. Development of the method and application to AI Phoenicis
• The Evolution of Rotation and Magnetic Activity in 94 Aqr Aa from Asteroseismology with TESS
• The G+M eclipsing binary V530 Orionis: A stringent test of magnetic stellar evolution models for low-mass stars
• HIDES spectroscopy of bright detached eclipsing binaries from the $Kepler$ field - II. Double- and triple-lined objects
• Testing Angular Momentum Transport and Wind Loss in Intermediate Mass Core Helium Burning Stars
• Automated approach to measure stellar inclinations: validation through large-scale measurements on the red giant branch
• Von Zeipel - Lidov - Kozai cycles in action: $Kepler$ triples with eclipse depth variations: KICs 6964043, 5653126, 5731312 and 8023317
• Evolution of the gravity offset of mixed modes in RGB stars
• On attempting to automate the identification of mixed dipole modes for subgiant stars
• Asteroseismic and orbital analysis of the triple star system HD 188753 observed by Kepler
• KOI-3890: A high mass-ratio asteroseismic red-giant$+$M-dwarf eclipsing binary undergoing heartbeat tidal interactions
• Oscillating red-giant stars in eccentric binary systems

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• Mode Mixing and Rotational Splittings: II. Reconciling Different Approaches to Mode Coupling
• Then and now: A new look at the eclipse timing variations of hierarchical triple star candidates in the primordial $Kepler$-field, revisited by TESS
• TIC 290061484: A Triply Eclipsing Triple System with the Shortest Known Outer Period of 24.5 Days
• Ten new, ultracompact triply eclipsing triple star systems
• Spectroscopy of Eclipsing Compact Hierarchical Triples I
• A differentiable N-body code for transit timing and dynamical modelling -- II. Photodynamics
• FRA -- A new Fast, Robust and Automated pipeline for the detection and measurement of solar-like oscillations in time-series photometry of red-giant stars
• Discovery of a compact hierarchical triple main-sequence star system while searching for binary stars with compact objects
• Halo Photometry and Asteroseismology for 98 of the Brightest Stars Observed by TESS
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