Age determination of the HR8799 planetary system using asteroseismology

Abstract

Discovery of the first planetary system by direct imaging around HR8799 has made the age determination of the host star a very important task. This determination is the key to derive accurate masses of the planets and to study the dynamical stability of the system. The age of this star has been estimated using different procedures. In this work we show that some of these procedures have problems and large uncertainties, and the real age of this star is still unknown, needing more observational constraints. Therefore, we have developed a comprehensive modeling of HR8799, and taking advantage of its gamma Doradus-type pulsations, we have estimated the age of the star using asteroseismology. The accuracy in the age determination depends on the rotation velocity of the star, and therefore an accurate value of the inclination angle is required to solve the problem. Nevertheless, we find that the age estimate for this star previously published in the literature ([30,160] Myr) is unlikely, and a more accurate value might be closer to the Gyr. This determination has deep implications on the value of the mass of the objects orbiting HR8799. An age around $\approx$ 1 Gyr implies that these objects are brown dwarfs.

5 pages, 3 figures, accepted in MNRAS Letters

References in corpus (15)

• Validation of the new Hipparcos reduction
• Direct Imaging of Multiple Planets Orbiting the Star HR 8799
• VOSA: Virtual Observatory SED Analyzer. An application to the Collinder 69 open cluster
• Debris Disk Evolution Around A Stars
• Spitzer IRS Spectroscopy of IRAS-Discovered Debris Disks
• Characterization of Dusty Debris Disks: the IRAS and Hipparcos Catalogs
• Probing the properties of convective cores through g modes: high-order g modes in SPB and gamma Doradus stars
• Nearby debris disk systems with high fractional luminosity reconsidered
• CESAM: a free code for stellar evolution calculations
• A possible architecture of the planetary system HR 8799
• The CoRoT Evolution and Seismic Tools Activity: Goals and Tasks
• Inter-comparison of the g-, f- and p-modes calculated using different oscillation codes for a given stellar model
• Granada oscillation Code (GraCo)
• A comprehensive asteroseismic modelling of the high-amplitude delta Scuti star RV Arietis
• Discovery and application of Frequency Ratio Method to the new multiperiodic gamma Dor star HD 218427

Cited by in corpus (35)

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• Near-Infrared Spectroscopy of the Extrasolar Planet HR 8799 b
• A uniform asteroseismic analysis of 22 solar-type stars observed by Kepler
• Constraining the initial entropy of directly-detected exoplanets
• First Light LBT AO Images of HR 8799 bcde at 1.65 and 3.3 Microns: New Discrepancies between Young Planets and Old Brown Dwarfs
• Reconnaissance of the HR 8799 Exosolar System I: Near IR Spectroscopy
• Atmospheric Retrieval Analysis of the Directly Imaged Exoplanet HR 8799b
• The CHARA Array Angular Diameter of HR 8799 Favors Planetary Masses for Its Imaged Companions
• Resolved Submillimeter Observations of the HR 8799 and HD 107146 Debris Disks
• Measuring mean densities of delta Scuti stars with asteroseismology. Theoretical properties of large separations using TOUCAN
• The Ages of A-Stars I: Interferometric Observations and Age Estimates for Stars in the Ursa Major Moving Group
• Debris Distribution in HD 95086 - A Young Analog of HR 8799
• High-Mass, Four-Planet Models for HR 8799: Constraining the Orbital Inclination and Age of the System
• Determination of the inclination of the multi-planet hosting star HR8799 using asteroseismology
• Could the planets around HR 8799 be brown dwarfs?
• Four-of-a-kind? Comprehensive atmospheric characterisation of the HR 8799 planets with VLTI/GRAVITY
• The Dawes Review 3: The Atmospheres of Extrasolar Planets and Brown Dwarfs
• The Scattered Disc of HR 8799
• An evaluation of the membership probability of 212 $\lambda$ Boo stars: I. A Catalogue
• Fly-by encounters between two planetary systems II: Exploring the interactions of diverse planetary system architectures
• Dynamical Mass of the Exoplanet Host Star HR 8799
• JWST-TST High Contrast: Living on the Wedge, or, NIRCam Bar Coronagraphy Reveals CO${}_2$ in the HR 8799 and 51 Eri Exoplanets' Atmospheres
• TOI-2046b, TOI-1181b and TOI-1516b, three new hot Jupiters from \textit{TESS}: planets orbiting a young star, a subgiant and a normal star
• MOST light-curve analysis of the gamma Dor pulsator HR 8799, showing resonances and amplitude variations
• Theoretical seismic properties of pre-main sequence gamma Doradus pulsators
• Direct-imaging Discovery of a Substellar Companion Orbiting the Accelerating Variable Star, HIP 39017
• Shaping HR8799's outer dust belt with an unseen planet
• Direct Imaging discovery of a second planet candidate around the possibly transiting planet host CVSO 30
• Clusters: age scales for stellar physics
• HD 54272, a classical lambda Bootis star and gamma Doradus pulsator
• Pulsating stars harbouring planets
• Taxonomy of the extrasolar planet
• The Directly-Imaged Exoplanet Host Star 51 Eridani is a Gamma Doradus Pulsator