Unveiling the Structure and Dynamics of Red Giants with Asteroseismology

Abstract

The Kepler mission observed many thousands of red giants. The long time series, some as long as the mission itself, have allowed us to study red giants with unprecedented detail. Given that red giants are intrinsically luminous, and hence can be observed from very large distances, knowing the properties of red giants, in particular ages, is of immense value for studies of the formation and evolution of the Galaxy, an endeavor known as "Galactic archaeology". In this article we review what we have learned about red giants using asteroseismic data. We start with the properties of the power spectrum and move on to internal structure and dynamics of these stars; we also touch upon unsolved issues in red-giant asteroseismology and the prospects of making further progress in understanding these stars.

arXiv commentAccepted for publication in Frontiers in Astronomy and Space Sciences

References in corpus (82)

• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• Gravity modes as a way to distinguish between hydrogen- and helium-burning red giant stars
• Fast core rotation in red-giant stars revealed by gravity-dominated mixed modes
• Spin down of the core rotation in red giants
• Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology
• Seismic evidence for a rapidly rotating core in a lower-giant-branch star observed with Kepler
• Slowing the Spins of Stellar Cores
• Seismic constraints on the radial dependence of the internal rotation profiles of six Kepler subgiants and young red giants
• The APOKASC Catalog: An Asteroseismic and Spectroscopic Joint Survey of Targets in the Kepler Fields
• Correcting stellar oscillation frequencies for near-surface effects
• Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and ages
• The Second APOKASC Catalog: The Empirical Approach
• Angular Momentum Transport in Stellar Interiors
• Angular momentum transport within evolved low-mass stars
• Calculating asteroseismic diagrams for solar-like oscillations
• Red giant masses and ages derived from carbon and nitrogen abundances
• Probing the core structure and evolution of red giants using gravity-dominated mixed modes observed with Kepler
• Asteroseismology of 16000 Kepler Red Giants: Global Oscillation Parameters, Masses, and Radii
• Characterization of the power excess of solar-like oscillations in red giants with Kepler
• The APOGEE red-clump catalog: Precise distances, velocities, and high-resolution elemental abundances over a large area of the Milky Way's disk
• A new correction of stellar oscillation frequencies for near-surface effects
• Mixed modes in red giants: a window on stellar evolution
• Tracing chemical evolution over the extent of the Milky Way's Disk with APOGEE Red Clump Stars
• Angular momentum transport in stellar interiors constrained by rotational splittings of mixed modes in red giants
• Young [$\alpha$/Fe]-enhanced stars discovered by CoRoT and APOGEE: What is their origin?
• Mixed modes in red-giant stars observed with CoRoT
• Granulation in Red Giants: observations by the Kepler mission and 3D convection simulations
• Period spacings in red giants II. Automated measurement
• Asteroseismology Can Reveal Strong Internal Magnetic Fields in Red Giant Stars
• Giant star seismology
• Core rotation braking on the red giant branch for various mass ranges
• Oscillation mode frequencies of 61 main sequence and subgiant stars observed by Kepler
• A prevalence of dynamo-generated magnetic fields in the cores of intermediate-mass stars
• Oscillation frequencies for 35 \Kepler solar-type planet-hosting stars using Bayesian techniques and machine learning
• The asteroseismic potential of Kepler: first results for solar-type stars
• Pulsating red giant stars in eccentric binary systems discovered from Kepler space-based photometry
• DIAMONDS: a new Bayesian Nested Sampling tool. Application to Peak Bagging of solar-like oscillations
• Seismic diagnostics for transport of angular momentum in stars 2. Interpreting observed rotational splittings of slowly-rotating red giant stars
• Evolutionary influences on the structure of red-giant acoustic oscillation spectra from 600d of Kepler observations
• Period spacings in red giants I. Disentangling rotation and revealing core structure discontinuities
• Understanding angular momentum transport in red giants: the case of KIC 7341231
• Testing the Asteroseismic Mass Scale Using Metal-Poor Stars Characterized with APOGEE and Kepler
• Surface-effect corrections for solar-like oscillations using 3D hydrodynamical simulations
• Internal rotation of the red-giant star KIC 4448777 by means of asteroseismic inversion
• Significantly improving stellar mass and radius estimates: A new reference function for the Δν scaling relation
• Constraining the efficiency of angular momentum transport with asteroseismology of red giants: the effect of stellar mass
• Structural glitches near the cores of red giants revealed by oscillations in g-mode period spacings from stellar models
• Galactic Archaeology with asteroseismic ages. II. Confirmation of a delayed gas infall using Bayesian analysis based on MCMC methods
• Dipole modes with depressed amplitudes in red giants are mixed modes
• Angular momentum redistribution by mixed modes in evolved low-mass stars. II. Spin-down of the core of red giants induced by mixed modes
• Deep Learning Classification in Asteroseismology Using an Improved Neural Network: Results on 15000 Kepler Red Giants and Applications to K2 and TESS Data
• Modelling Kepler Red Giants in Eclipsing Binaries:Calibrating the Mixing Length Parameter with Asteroseismology
• A large and pristine sample of standard candles across the Milky Way: ~100,000 red clump stars with 3% contamination
• A New Method for the Asteroseismic Determination of the Evolutionary State of Red-Giant Stars
• Study of KIC 8561221 observed by Kepler: an early red giant showing depressed dipolar modes
• New light on the Gaia DR2 parallax zero-point: influence of the asteroseismic approach, in and beyond the Kepler field
• Angular momentum redistribution by mixed modes in evolved low-mass stars. I. Theoretical formalism
• Probing the deep end of the Milky Way with \emph{Kepler}: Asteroseismic analysis of 854 faint Red Giants misclassified as Cool Dwarfs
• Near-degeneracy effects on the frequencies of rotationally-split mixed modes in red giants
• Age-chemical abundance structure of the Galaxy I: Evidence for a late accretion event in the outer disc at z ~ 0.6
• Origin of $\alpha$-rich young stars: clues from C, N and O
• Semi-analytic Expressions for the Isolation and Coupling of Mixed Modes
• On the asymptotic acoustic-mode phase in red-giant stars and its dependence on evolutionary state
• Seismic probing of the first dredge-up event through the eccentric red-giant & red-giant spectroscopic binary KIC9163796
• Insights from the APOKASC Determination of the Evolutionary State of Red-Giant Stars by consolidation of different methods
• Using red clump stars to correct the Gaia DR1 parallaxes
• Surface effects on the red giant branch
• The Helium Abundance of NGC 6791 from Modeling of Stellar Oscillations
• Investigating surface correction relations for RGB stars
• The rotational shear layer inside the early red-giant star KIC 4448777
• Effects of a strong magnetic field on internal gravity waves: trapping, phase mixing, reflection and dynamical chaos
• Isochrone fitting in the Gaia era
• Modeling the Asteroseismic Surface Term across the HR Diagram
• Automated asteroseismic peak detections
• Mitigating the mass dependence in the $\Delta \nu$ scaling relation of red-giant stars
• Core-Envelope Coupling in Intermediate-Mass Core-Helium Burning Stars
• Explaining Deviations from the Scaling Relationship of the Large Frequency Separation
• CoRoT and Kepler results: Solar-like oscillators
• Torsional Alfvén resonances as an efficient damping mechanism for non-radial oscillations in red giant stars
• Structural and Evolutionary Diagnostics from Asteroseismic Phase Functions
• Asteroseismic sensitivity to internal rotation along the red-giant branch
• Constraining the core-rotation rate in red-giant stars from Kepler space photometry

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• Discovery of post-mass-transfer helium-burning red giants using asteroseismology
• Disentangling the origin of chemical differences using GHOST
• Toward fully compressible numerical simulations of stellar magneto-convection with the RAMSES code
• Testing the wavelength dependence of oscillations and granulation in red giants using Kepler and TESS
• The oscillation properties of the Blue Large Amplitude Pulsators (BLAPs): relative change rate of periods, excitations, and period relations
• Damping of Oscillations in Red Giants by Resonant Mode Coupling