The Age of the Directly-Imaged Planet Host Star $\kappa$ Andromedae Determined From Interferometric Observations

Abstract

$\kappa$ Andromedae, an early type star that hosts a directly imaged low mass companion, is expected to be oblate due to its rapid rotational velocity ($v\sin i$ = $\sim$162 $\mathrm{km}{\mathrm{s}}^{-1}$). We observed the star with the CHARA Array's optical beam combiner, PAVO, measuring its size at multiple orientations and determining its oblateness. The interferometric measurements, combined with photometry and this $v\sin i$ value are used to constrain an oblate star model that yields the fundamental properties of the star and finds a rotation speed that is $\sim$85\% of the critical rate and a low inclination of $\sim$30${}^{\circ }$. Three modeled properties (the average radius, bolometric luminosity, and equatorial velocity) are compared to MESA evolution models to determine an age and mass for the star. In doing so, we determine an age for the system of 47${}_{-40}^{+27}$ Myr. Based on this age and previous measurements of the companion's temperature, the BHAC15 evolution models imply a mass for the companion of 22${}_{-9}^{+8}$ M${}_{\mathrm{J}}$.

arXiv comment8 pages, 3 figures. Accepted for publication in ApJ Letters

References in corpus (28)

• Modules for Experiments in Stellar Astrophysics (MESA)
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• Validation of the new Hipparcos reduction
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• A new extensive library of PHOENIX stellar atmospheres and synthetic spectra
• Grids of stellar models with rotation - I. Models from 0.8 to 120 Msun at solar metallicity (Z = 0.014)
• Evolutionary models for cool brown dwarfs and extrasolar giant planets. The case of HD 20945
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• The Occurrence and Architecture of Exoplanetary Systems
• First Results from the CHARA Array. II. A Description of the Instrument
• A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood
• The Deuterium-Burning Mass Limit for Brown Dwarfs and Giant Planets
• The Tucana/Horologium, Columba, AB Doradus, and Argus Associations: New Members and Dusty Debris Disks
• Interferometric Observations of Rapidly Rotating Stars
• Gravity darkening in rotating stars
• On the Galactic Disk Metallicity Distribution from Open Clusters I. New Catalogues and Abundance Gradient
• Rotational velocities of A-type stars. III. Velocity distributions
• Coude-feed stellar spectral library - atmospheric parameters
• Direct Imaging Discovery of a `Super-Jupiter' Around the late B-Type Star Kappa And
• The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets
• Bayesian Ages for Early-Type Stars from Isochrones Including Rotation, and a Possible Old Age for the Hyades
• Deuterium Burning in Massive Giant Planets and Low-Mass Brown Dwarfs formed by Core-Nucleated Accretion
• HAT-P-57b: A Short-Period Giant Planet Transiting A Bright Rapidly Rotating A8V Star Confirmed Via Doppler Tomography
• The Kappa Andromedae System: New Constraints on the Companion Mass, System Age & Further Multiplicity
• The Ages of A-Stars I: Interferometric Observations and Age Estimates for Stars in the Ursa Major Moving Group
• Deuterium burning in objects forming via the core accretion scenario - Brown dwarfs or planets?
• Characterization of the gaseous companion κ Andromedae b: New Keck and LBTI high-contrast observations
• Determining the Physical Properties of the B Stars II. Calibration of Synthetic Photometry

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