Determining stellar parameters of asteroseismic targets: going beyond the use of scaling relations

Abstract

Asteroseismic parameters allow us to measure the basic stellar properties of field giants observed far across the Galaxy. Most of such determinations are, up to now, based on simple scaling relations involving the large frequency separation, Δν, and the frequency of maximum power, ν${}_{max}$. In this work, we implement Δν and the period spacing, ΔP, computed along detailed grids of stellar evolutionary tracks, into stellar isochrones and hence in a Bayesian method of parameter estimation. Tests with synthetic data reveal that masses and ages can be determined with typical precision of 5 and 19 per cent, respectively, provided precise seismic parameters are available. Adding independent information on the stellar luminosity, these values can decrease down to 3 and 10 per cent respectively. The application of these methods to NGC 6819 giants produces a mean age in agreement with those derived from isochrone fitting, and no evidence of systematic differences between RGB and RC stars. The age dispersion of NGC 6819 stars, however, is larger than expected, with at least part of the spread ascribable to stars that underwent mass-transfer events.

17 pages, 13 figures, accepted for publication in MNRAS

References in corpus (4)

• Synthetic Stellar Photometry - I. General considerations and new transformations for broad-band systems
• Prospects for asteroseismic inference on the envelope helium abundance in red giant stars
• On the asymptotic acoustic-mode phase in red-giant stars and its dependence on evolutionary state
• On the Interpretation of Sub-Giant Branch Morphologies of Intermediate-Age Star Clusters with Extended Main Sequence Turnoffs

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• Changing the ${\nu }_{\max }$ Scaling Relation: The Need For a Mean Molecular Weight Term
• Testing asteroseismology with Gaia DR2: Hierarchical models of the Red Clump
• Detection and characterisation of oscillating red giants: first results from the TESS satellite
• The masses of retired A stars with asteroseismology: Kepler and K2 observations of exoplanet hosts
• The Curious Case of KOI 4: Confirming Kepler's First Exoplanet
• Determining the Best Method of Calculating the Large Frequency Separation For Stellar Models
• TESS Asteroseismic Analysis of the Known Exoplanet Host Star HD 222076
• Stellar atmospheric parameters of FGK-type stars from high-resolution optical and near-infrared CARMENES spectra
• KOI-3890: A high mass-ratio asteroseismic red-giant$+$M-dwarf eclipsing binary undergoing heartbeat tidal interactions
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