Inference of stellar parameters from brightness variations

Abstract

It has been demonstrated that the time variability of a star's brightness at different frequencies can be used to infer its surface gravity, radius, mass, and age. With large samples of light curves now available from Kepler and K2, and upcoming surveys like TESS, we wish to quantify the overall information content of this data and identify where the information resides. As a first look into this question we ask which stellar parameters we can predict from the brightness variations in red-giant stars data and to what precision, using a data-driven model. We demonstrate that the long-cadence (30-minute) Kepler light curves for 2000 red-giant stars can be used to predict their $T_{\mathrm{eff}}$ and $\log g$. Our inference makes use of a data-driven model of a part of the autocorrelation function (ACF) of the light curve, where we posit a polynomial relationship between stellar parameters and the ACF pixel values. We find that this model, trained using 1000 stars, can be used to recover the temperature $T_{\mathrm{eff}}$ to $<$100 K, the surface gravity to $<$ 0.1 dex, and the asteroseismic power-spectrum parameters ${\nu }_{\max }$ and $\mathrm{\Delta }\nu$ to $<11$ $\mu$Hz and $<0.9$ $\mu$Hz ($\lesssim$ 15\%). We recover $T_{\mathrm{eff}}$ from range of time-lags 0.045 $<$ $T_{\mathrm{lag}}$ $<$ 370 days and the $\log g$, ${\nu }_{\max }$ and $\mathrm{\Delta }\nu$ from the range 0.045 $<$ $T_{\mathrm{lag}}$ $<$ 35 days. We do not discover any information about stellar metallicity. The information content of the data about each parameter is empirically quantified using this method, enabling comparisons to theoretical expectations about convective granulation.

arXiv comment10 pages, 7 Figures, submitted to ApJ

References in corpus (49)

• The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
• The New Galaxy: Signatures of its Formation
• ASPCAP: The Apogee Stellar Parameter and Chemical Abundances Pipeline
• Measuring the rotation period distribution of field M-dwarfs with Kepler
• Testing Scaling Relations for Solar-Like Oscillations from the Main Sequence to Red Giants using Kepler Data
• The Cannon: A data-driven approach to stellar label determination
• Asteroseismic fundamental properties of solar-type stars observed by the NASA Kepler Mission
• The APOKASC Catalog: An Asteroseismic and Spectroscopic Joint Survey of Targets in the Kepler Fields
• Calculating asteroseismic diagrams for solar-like oscillations
• The connection between stellar granulation and oscillation as seen by the Kepler mission
• Asteroseismology and Gaia: Testing Scaling Relations Using 2200 Kepler Stars with TGAS Parallaxes
• Standing on the shoulders of Dwarfs: the $Kepler$ asteroseismic LEGACY sample I - oscillation mode parameters
• Red giant masses and ages derived from carbon and nitrogen abundances
• Solar-like oscillations in low-luminosity red giants: first results from Kepler
• Asteroseismology of 16000 Kepler Red Giants: Global Oscillation Parameters, Masses, and Radii
• The relation between $\Delta \nu$ and ${\nu }_{max}$ for solar-like oscillations
• Characterization of the power excess of solar-like oscillations in red giants with Kepler
• The underlying physical meaning of the ${\nu }_{\max }-{\nu }_{\mathrm{c}}$ relation
• Spectroscopic determination of masses (and implied ages) for red giants
• Stellar population synthesis based modelling of the Milky Way using asteroseismology of 13000 Kepler red giants
• 3D Hydrodynamical Simulations of Surface Convection in Red Giant Stars. Impact on spectral line formation and abundance analysis
• Asteroseismology of red giants from the first four months of Kepler data: Global oscillation parameters for 800 stars
• Granulation in Red Giants: observations by the Kepler mission and 3D convection simulations
• Verifying asteroseismically determined parameters of Kepler stars using hipparcos parallaxes: self-consistent stellar properties and distances
• Confirming chemical clocks: asteroseismic age dissection of the Milky Way disk(s)
• Oscillation frequencies for 35 \Kepler solar-type planet-hosting stars using Bayesian techniques and machine learning
• Measuring the vertical age structure of the Galactic disc using asteroseismology and SAGA
• An observational correlation between stellar brightness variations and surface gravity
• The First APOKASC Catalog of Kepler Dwarf and Subgiant Stars
• The Correlation Between Mixing Length and Metallicity on the Giant Branch: Implications for Ages in the Gaia Era
• Automated preparation of Kepler time series of planet hosts for asteroseismic analysis
• Solar-like oscillations in red giants observed with Kepler: comparison of global oscillation parameters from different methods
• Testing the Asteroseismic Mass Scale Using Metal-Poor Stars Characterized with APOGEE and Kepler
• Significantly improving stellar mass and radius estimates: A new reference function for the Δν scaling relation
• Changing the ${\nu }_{\max }$ Scaling Relation: The Need For a Mean Molecular Weight Term
• The K2 Galactic Archaeology Program Data Release 1: Asteroseismic results from Campaign 1
• Interaction Between Convection and Pulsation
• Metallicity effect on stellar granulation detected from oscillating red giants in open clusters
• Limits on surface gravities of Kepler planet-candidate host stars from non-detection of solar-like oscillations
• A Granulation "Flicker"-based Measure of Stellar Surface Gravity
• Observations of intensity fluctuations attributed to granulation and faculae on Sun-like stars from the Kepler mission
• Stellar Granulation as the Source of High-Frequency Flicker in Kepler Light Curves
• Using Stellar Densities to Evaluate Transiting Exoplanetary Candidates
• Stellar granulation as seen in disk-integrated intensity. II. Theoretical scaling relations compared with observations
• Nonlinear seismic scaling relations
• Data preparation for asteroseismology with TESS
• Rotation Periods of Wide Binaries in the Kepler Field
• Flicker as a tool for characterizing planets through Asterodensity Profiling
• Hydrodynamical model atmospheres: Their impact on stellar spectroscopy and asteroseismology of late-type stars

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• Astroconformer: The Prospects of Analyzing Stellar Light Curves with Transformer-Based Deep Learning Models
• The Swan: Data-Driven Inference of Stellar Surface Gravities for Cool Stars from Photometric Light Curves
• Solar Photospheric Spectrum Microvariability I. Theoretical searches for proxies of radial-velocity jittering
• Scaling relations of convective granulation noise across the HR diagram from 3D stellar atmosphere models