Seismic signature of envelope penetrative convection: the CoRoT star HD 52265

Abstract

Aims: We aim at characterizing the inward transition from convective to radiative energy transport at the base of the convective envelope of the solar-like oscillator HD 52265 recently observed by the CoRoT satellite. Methods: We investigated the origin of one specific feature found in the HD 52265 frequency spectrum. We modelled the star to derive the internal structure and the oscillation frequencies that best match the observations and used a seismic indicator sensitive to the properties of the base of the envelope convection zone. Results: The seismic indicators clearly reveal that to best represent the observed properties of HD 52265, models must include penetrative convection below the outer convective envelope. The penetrative distance is estimated to be $\sim 0.95H_P$, which corresponds to an extent over a distance representing 6.0 per cents of the total stellar radius, significantly larger than what is found for the Sun. The inner boundary of the extra-mixing region is found at $0.800\pm 0.004R$ where $R=1.3R_{\odot }$ is the stellar radius. Conclusions: These results contribute to the tachocline characterization in stars other than the Sun.

4 pages, 4 figures, accepted for publication in Astronomy & Astrophysics Letters

References in corpus (6)

• Correcting stellar oscillation frequencies for near-surface effects
• CESAM: a free code for stellar evolution calculations
• An asteroseismic signature of helium ionization
• The Liege Oscillation Code
• Accurate p-mode measurements of the G0V metal-rich CoRoT target HD 52265
• Precise Modeling of the Exoplanet Host Star and CoRoT Main Target HD 52265

Cited by in corpus (25)

• The PLATO 2.0 Mission
• A new correction of stellar oscillation frequencies for near-surface effects
• Asteroseismology of solar-type stars
• Asteroseismology for "à la carte" stellar age-dating and weighing: Age and mass of the CoRoT exoplanet host HD 52265
• Stellar ages and convective cores in field main-sequence stars: first asteroseismic application to two Kepler targets
• Measuring the extent of convective cores in low-mass stars using Kepler data: towards a calibration of core overshooting
• Rotation periods and seismic ages of KOIs - comparison with stars without detected planets from Kepler observations
• New PARSEC database of alpha-enhanced stellar evolutionary tracks and isochrones I. Calibration with 47 Tuc (NGC104) and the improvement on RGB bump
• How accurate are stellar ages based on stellar models? II. The impact of asteroseismology
• In-depth study of 16CygB using inversion techniques
• Convective boundary mixing in low- and intermediate-mass stars I. Core properties from pressure-mode asteroseismology
• Constraints on the structure of 16 Cyg A and 16 Cyg B using inversion techniques
• Modeling Convective Core Overshoot and Diffusion in Procyon Constrained by Asteroseismic Data
• New Insights for High-precision Asteroseismology: Acoustic Radius of KIC 6225718
• Constraining convective regions with asteroseismic linear structural inversions
• Buoyancy glitches in pulsating stars revisited
• Multi-cavity gravito-acoustic modes in stars: A general analytical resonance condition
• Glitches in solar-like oscillating F-type stars: Theoretical signature of the base of the convective envelope on the ratios $r_{010}$
• Impact of asteroseismology on improving stellar ages determination
• Local perturbations of the upper layers of a Sun-like star: the impact on the acoustic oscillation spectrum
• Modeling of two CoRoT solar analogues constrained by seismic and spectroscopic analysis
• Asteroseismic Structure Inversions of Main-Sequence Solar-like Oscillators with Convective Cores
• Stellar oscillations - the adiabatic case
• Physical interpretation of the oscillation spectrum on the RGB and AGB
• On the stellar core physics of the 16 Cyg binary system: constraining the central hydrogen abundance using asteroseismology