The K2 M67 Study: Revisiting old friends with K2 reveals oscillating red giants in the open cluster M67

Abstract

Observations of stellar clusters have had a tremendous impact in forming our understanding of stellar evolution. The open cluster M67 has a particularly important role as a calibration benchmark for stellar evolution theory due to its near solar composition and age. As a result, it has been observed extensively, including attempts to detect solar-like oscillations in its main sequence and red giant stars. However, any asteroseismic inference has so far remained elusive due to the difficulty in measuring these extremely low amplitude oscillations. Here we report the first unambiguous detection of solar-like oscillations in the red giants of M67. We use data from the Kepler ecliptic mission, K2, to measure the global asteroseismic properties. We find a model-independent seismic-informed distance of 816+/-11pc, or (m-M)o=9.57+/-0.03mag, an average red-giant mass of 1.36+/-0.01Msun, in agreement with the dynamical mass from an eclipsing binary near the cluster turn-off, and ages of individual stars compatible with isochrone fitting. We see no evidence of strong mass loss on the red giant branch. We also determine seismic log g of all the cluster giants with a typical precision of ~0.01dex. Our results generally show good agreement with independent methods and support the use of seismic scaling relations to determine global properties of red giant stars with near solar metallicity. We further illustrate that the data are of such high quality, that future work on individual mode frequencies should be possible, which would extend the scope of seismic analysis of this cluster.

arXiv commentAccepted by ApJ. 7 pages, 5 figures, 2 tables

References in corpus (41)

• The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
• The K2 Mission: Characterization and Early results
• A large stellar evolution database for population synthesis studies. I. Scaled solar models and isochrones
• An absolutely calibrated effective temperature scale from the InfraRed Flux Method
• A Technique for Extracting Highly Precise Photometry for the Two-Wheeled Kepler Mission
• Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology
• Asteroseismology of old open clusters with Kepler: direct estimate of the integrated RGB mass loss in NGC6791 and NGC6819
• The K2 Ecliptic Plane Input Catalog (EPIC) and Stellar Classifications of 138,600 Targets in Campaigns 1-8
• Calculating asteroseismic diagrams for solar-like oscillations
• The connection between stellar granulation and oscillation as seen by the Kepler mission
• Synthetic Stellar Photometry - I. General considerations and new transformations for broad-band systems
• Planetary Candidates from the First Year of the K2 Mission
• Galactic archaeology: mapping and dating stellar populations with asteroseismology of red-giant stars
• Stellar population synthesis based modelling of the Milky Way using asteroseismology of 13000 Kepler red giants
• 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
• Radius determination of solar-type stars using asteroseismology: What to expect from the Kepler mission
• The universal red-giant oscillation pattern; an automated determination with CoRoT data
• Age and helium content of the open cluster NGC 6791 from multiple eclipsing binary members. II. age dependencies and new insights
• Asteroseismology of the open clusters NGC 6791, NGC 6811, and NGC 6819 from nineteen months of Kepler photometry
• Sounding open clusters: asteroseismic constraints from Kepler on the properties of NGC 6791 and NGC 6819
• Amplitudes of solar-like oscillations: a new scaling relation
• Rotation periods for cool stars in the 4 Gyr-old open cluster M67, the solar-stellar connection, and the applicability of gyrochronology to at least solar age
• Stellar Radial Velocities in the Old Open Cluster M67 (NGC 2682) I. Memberships, Binaries, and Kinematics
• Stroemgren survey for Asteroseismology and Galactic Archaeology: let the SAGA begin
• Oscillating red giants observed during Campaign 1 of the Kepler K2 mission: New prospects for galactic archaeology
• An asteroseismic membership study of the red giants in three open clusters observed by Kepler: NGC6791, NGC6819, and NGC6811
• Abundances of four open clusters from solar stars
• Deep 2MASS Photometry of M67 and Calibration of the Main Sequence J-Ks Color Difference as an Age Indicator
• Non-radial oscillations in M-giant semi-regular variables: Stellar models and Kepler observations
• Significantly improving stellar mass and radius estimates: A new reference function for the Δν scaling relation
• Asteroseismic inferences on red giants in open clusters NGC 6791, NGC 6819 and NGC 6811 using Kepler
• Detection of solar-like oscillations from Kepler photometry of the open cluster NGC 6819
• Amplitudes of solar-like oscillations: constraints from red giants in open clusters observed by Kepler
• Multisite campaign on the open cluster M67. II. Evidence for solar-like oscillations in red giant stars
• Oscillation mode lifetimes in ksi Hydrae: Will strong mode damping limit asteroseismology of red giant stars?
• WOCS 40007: A Detached Eclipsing Binary near the Turnoff of the Open Cluster NGC 6819
• A Long-Period Totally Eclipsing Binary Star at the Turnoff of the Open Cluster NGC 6819 Discovered with Kepler
• Asteroseismology of 1523 misclassified red giants using $\text{Kepler}$ data
• Asteroseismology of the Hyades with K2: first detection of main-sequence solar-like oscillations in an open cluster
• Variability Among Stars in the M 67 Field from Kepler/K2-Campaign-5 Light Curves

Cited by in corpus (64)

• The Second APOKASC Catalog: The Empirical Approach
• Asteroseismology and Gaia: Testing Scaling Relations Using 2200 Kepler Stars with TGAS Parallaxes
• The orbital eccentricity of small planet systems
• Age dissection of the Milky Way discs: red giants in the Kepler field
• PARSEC V2.0: Stellar tracks and isochrones of low and intermediate mass stars with rotation
• Accuracy and precision of industrial stellar abundances
• PLATO as it is: a legacy mission for Galactic archaeology
• TESS Hunt for Young and Maturing Exoplanets (THYME) VI: an 11 Myr giant planet transiting a very low-mass star in Lower Centaurus Crux
• The K2 Galactic Archaeology Program Data Release 1: Asteroseismic results from Campaign 1
• Chemical Abundances of Main-Sequence, Turn-off, Subgiant and red giant Stars from APOGEE spectra I: Signatures of Diffusion in the Open Cluster M67
• Deep Learning Classification in Asteroseismology Using an Improved Neural Network: Results on 15000 Kepler Red Giants and Applications to K2 and TESS Data
• Blue Lurkers: Hidden Blue Stragglers on the M67 Main Sequence Identified from their Kepler/K2 Rotation Periods
• MINESweeper: Spectrophotometric Modeling of Stars in the Gaia Era
• The BAyesian STellar Algorithm (BASTA): a fitting tool for stellar studies, asteroseismology, exoplanets, and Galactic archaeology
• New light on the Gaia DR2 parallax zero-point: influence of the asteroseismic approach, in and beyond the Kepler field
• Mapping the Galactic disk with the LAMOST and Gaia Red clump sample: I: precise distances, masses, ages and 3D velocities of $\sim$ 140000 red clump stars
• A 4 Gyr M-dwarf Gyrochrone from CFHT/MegaPrime Monitoring of the Open Cluster M67
• The GALAH survey: Chemical Tagging of Star Clusters and New Members in the Pleiades
• Discovery of post-mass-transfer helium-burning red giants using asteroseismology
• UVIT Open Cluster Study. II. Detection of extremely low mass white dwarfs and post-mass transfer binaries in M67
• K2 space photometry reveals rotational modulation and stellar pulsations in chemically peculiar A and B stars
• High Mass-ratio Binary Population in Open Clusters: Segregation of early type binaries and an increasing binary fraction with mass
• The [Y/Mg] clock works for evolved solar metallicity stars
• Integrated Mass Loss of Evolved Stars in M4 using Asteroseismology
• Using red clump stars to correct the Gaia DR1 parallaxes
• Asteroseismology of the multiple stellar populations in the Globular Cluster M4
• Weighing in on the masses of retired A stars with asteroseismology: K2 observations of the exoplanet-host star HD 212771
• Ultraviolet stellar population of the old open cluster M67 (NGC 2682)
• Stellar ages and masses in the solar neighbourhood: Bayesian analysis using spectroscopy and Gaia DR1 parallaxes
• Asteroseismology of the Hyades red giant and planet host epsilon Tauri
• UOCS. III. UVIT catalogue of open clusters with machine learning based membership using \textit{Gaia} EDR3 astrometry
• Systematic Differences in Spectroscopic Analysis of Red Giants
• Isochrone fitting to the open cluster M67 in the era of Gaia and improved model physics
• Ensemble Properties of the White Dwarf Population of the Old, Solar Metallicity Open Star Cluster Messier 67
• No "Maunder minimum" candidates in M67: mitigating interstellar contamination of chromospheric emission lines
• An asteroseismic age estimate of the open cluster NGC 6866 using Kepler and Gaia
• Variability in the Massive Open Cluster NGC 1817 from K2: A Rich Population of Asteroseismic Red Clump, Eclipsing Binary, and Main Sequence Pulsating Stars
• Comparison of the Asteroseismic Mass Scale of Red Clump Giants with Photometric Mass Estimates
• Precise Masses, Ages of ~1.0 million RGB and RC stars observed by the LAMOST
• The GALAH+ Survey: A New Library of Observed Stellar Spectra Improves Radial Velocities and Hints at Motions within M67
• Identification, mass and age of primary red clump stars from spectral features derived with the LAMOST DR7
• Star Cluster Ages in the Gaia Era
• The K2 M67 Study: Precise Mass for a Turnoff Star in the Old Open Cluster M67
• A Unified Exploration of the Chronology of the Galaxy
• Climbing the cosmic ladder with stellar twins in RAVE with Gaia
• Connecting integrated RGB mass loss from asteroseismology and globular clusters
• Evidence that Mass Loss on the Red Giant Branch Decreases with Metallicity
• The K2 Asteroseismic KEYSTONE sample of Dwarf and Subgiant Solar-Like Oscillators. I: Data and Asteroseismic parameters
• Asteroseismic Study of Subgiants and Giants of the Open Cluster M67 using Kepler/K2: Expanded Sample and Precise Masses
• M67 Blue Stragglers with High-resolution Infrared Spectroscopy
• The Kepler Smear Campaign: Light curves for 102 Very Bright Stars
• The Blue Lurker WOCS 14020: A Long-Period Post-Common-Envelope Binary in M67 Originating from a Merger in a Triple System
• Mass and Age determination of the LAMOST data with different Machine Learning methods
• The K2 M67 Study: A Curiously Young Star in an Eclipsing Binary in an Old Open Cluster
• A GALAH View of the Chemical Homogeneity and Ages of Stellar Strings Identified in Gaia
• A study of Pulsation & Rotation in a sample of A-K type stars in the Kepler field
• Exploring the dependence of chemical traits on metallicity: chemical trends for red giant stars with asteroseismic ages
• Acoustic modes in M67 cluster stars trace deepening convective envelopes
• Constraining Planetary Migration and Tidal Dissipation with Coeval Hot Jupiters
• Identifying Uncertainties in Stellar Evolution Models Using the Open Cluster M67
• Asteroseismology of the young open cluster NGC 2516 II. Constraining cluster age using gravity-mode pulsators
• A uvbyCaHbeta CCD Analysis of the Open Cluster Standard, M67,and its Relation to NGC 752
• Spectroscopic and asteroseismic analysis of the secondary clump red giant HD 226808
• Asteroseismology of red giants in the globular cluster 47 Tuc using the HST