Detecting non-uniform period spacings in the Kepler photometry of gamma Doradus stars: methodology and case studies

Abstract

Context. The analysis of stellar oscillations is one of the most reliable ways to probe stellar interiors. Recent space missions such as Kepler have provided us with an opportunity to study these oscillations with unprecedented detail. For many multi-periodic pulsators such as γ Doradus stars, this led to the detection of dozens to hundreds of oscillation frequencies that could not be found from ground-based observations. Aims. We aim to detect non-uniform period spacings in the Fourier spectra of a sample of γ Doradus stars observed by Kepler. Such detection is complicated by both the large number of significant frequencies in the space photometry and by overlapping non-equidistant rotationally split multiplets. Methods. Guided by theoretical properties of gravity-mode oscillation of γ Doradus stars, we developed a period-spacing detection method and applied it to Kepler observations of a few stars, after having tested the performance from simulations. Results. The application of the technique resulted in the clear detection of non-uniform period spacing series for three out of the five treated Kepler targets. Disadvantages of the technique are also discussed, and include the disability to distinguish between different values of the spherical degree and azimuthal order of the oscillation modes without additional theoretical modelling. Conclusions. Despite the shortcomings, the method is shown to allow solid detections of period spacings for γ Doradus stars, which will allow future asteroseismic analyses of these stars.

arXiv comment10 pages, 13 figures, 2 tables. Accepted for publication in Astronomy & Astrophysics

References in corpus (29)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Kepler Mission Design, Realized Photometric Performance, and Early Science
• The CoRoT satellite in flight : description and performance
• Gravity modes as a way to distinguish between hydrogen- and helium-burning red giant stars
• GYRE: An open-source stellar oscillation code based on a new Magnus Multiple Shooting Scheme
• HERMES: a high-resolution fibre-fed spectrograph for the Mercator telescope
• Fast core rotation in red-giant stars revealed by gravity-dominated mixed modes
• Spin down of the core rotation in red giants
• Seismic constraints on the radial dependence of the internal rotation profiles of six Kepler subgiants and young red giants
• Probing the properties of convective cores through g modes: high-order g modes in SPB and gamma Doradus stars
• Gamma Doradus Stars: Defining a New Class of Pulsating Variables
• Asteroseismic measurement of surface-to-core rotation in a main sequence A star, KIC 11145123
• Asymptotic and measured large frequency separations
• Evidence for nonlinear resonant mode coupling in the Beta Cep star HD 180642 (V1449 Aql) from CoRoT space-based photometry
• Gravito-inertial and pressure modes detected in the B3 IV CoRoT target HD 43317
• KIC 10526294: a slowly rotating B star with rotationally split, quasi-equally spaced gravity modes
• First Kepler results on compact pulsators VIII: Mode identifications via period spacings in $g-$mode pulsating Subdwarf B stars
• Detection of a large sample of Gamma Dor stars from Kepler space photometry and high-resolution ground-based spectroscopy
• Physical properties of the eclipsing Delta Sct star KIC 10661783
• Denoising spectroscopic data by means of the improved Least-Squares Deconvolution method
• KIC 11285625: a double-lined spectroscopic binary with a gamma Dor pulsator discovered from Kepler space photometry
• Mode density and frequency extraction in the delta Scuti star HD 50844
• Spectrum Analysis of Bright Kepler late B- to early F- Stars
• Relationship between low and high frequencies in Delta Scuti stars: Photometric Kepler and spectroscopic analyses of the rapid rotator KIC 8054146
• Strong interactions between g- and p-modes in the hybrid gamma Doradus-delta Scuti CoRoT star ID105733033
• Spectroscopic Pulsational Frequency Identification and Mode Determination of γ Doradus Star HD 12901
• Visibility of unstable oscillation modes in a rapidly rotating B star
• Spectroscopic Pulsational Frequency and Mode Determination of the $\gamma$ Doradus Star HD 189631

Cited by in corpus (65)

• {\em Gaia}-derived luminosities of {\em Kepler} A/F stars and the pulsator fraction across the δ Scuti instability strip
• Sub-Inertial Gravity Modes in the B8V Star KIC 7760680 Reveal Moderate Core Overshooting and Low Vertical Diffusive Mixing
• Surface rotation and photometric activity for Kepler targets I. M and K main-sequence stars
• A unifying explanation of complex frequency spectra of gamma Dor, SPB and Be stars: combination frequencies and highly non-sinusoidal light curves
• Characterising the observational properties of δ Sct stars in the era of space photometry from the Kepler mission
• The first view of $\delta$ Scuti and $\gamma$ Doradus stars with the TESS mission
• Grid Search in Stellar Parameters: a software for spectrum analysis of single stars and binary systems
• Photometric detection of internal gravity waves in upper main-sequence stars. II. Combined TESS photometry and high-resolution spectroscopy
• Asteroseismic modelling of the two F-type hybrid pulsators KIC10080943A and KIC10080943B
• Asteroseismic masses, ages, and core properties of $\gamma$ Doradus stars using gravito-inertial dipole modes and spectroscopy
• Forward seismic modelling of the pulsating magnetic B-type star HD 43317
• Asteroseismic fingerprints of rotation and mixing in the slowly pulsating B8 V star KIC 7760680
• Period spacings of $\gamma$ Doradus pulsators in the \textit{Kepler} field: Rossby and gravity modes in 82 stars
• Rotation of the convective core in $\gamma$ Dor stars measured by dips in period spacings of g modes coupled with inertial modes
• Period spacings of $\gamma$ Doradus pulsators in the Kepler field: detection methods and application to 22 slow rotators
• Deciphering the oscillation spectrum of $\gamma$ Doradus and SPB stars
• KIC 10080943: a binary star with two $\gamma$ Doradus/$\delta$ Scuti hybrid pulsators. Analysis of the g modes
• Systematic search for stellar pulsators in the eclipsing binaries observed by Kepler
• KIC 10080943: An eccentric binary system containing two pressure- and gravity-mode hybrid pulsators
• Period spacings of gravity modes in rapidly rotating magnetic stars I. Axisymmetric fossil field with poloidal and toroidal components
• An astrophysical interpretation of the remarkable g-mode frequency groups of the rapidly rotating $\gamma$ Dor star, KIC 5608334
• The Age and Interior Rotation of Stars from Asteroseismology
• Gravity Modes Reveal the Internal Rotation of a Post-mass Transfer Gamma Doradus/Delta Scuti Hybrid Pulsator in Kepler Eclipsing Binary KIC 9592855
• Period spacings of gravity modes in rapidly rotating magnetic stars II. The case of an oblique dipolar fossil magnetic field
• Detecting axisymmetric magnetic fields using gravity modes in intermediate-mass stars
• Highlights of Discoveries for $\delta$ Scuti Variable Stars From the Kepler Era
• KIC5950759: a high-amplitude $\delta$ Sct star with amplitude and frequency modulation near the terminal age main sequence
• A comparison of the dynamical and model-derived parameters of the pulsating eclipsing binary KIC9850387
• Revisiting the pulsational characteristics of the exoplanet host star $\beta$ Pictoris
• TESS Data for Asteroseismology (T'DA) Stellar Variability Classification Pipeline: Set-Up and Application to the Kepler Q9 Data
• Unexpected series of regular frequency spacing of delta Scuti stars in the non-asymptotic regime -- I. The methodology
• Detection of period-spacing patterns due to the gravity modes of rotating dwarfs in the TESS southern continuous viewing zone
• Asteroseismology of the young open cluster NGC 2516 I: Photometric and spectroscopic observations
• Tango of celestial dancers: A sample of detached eclipsing binary systems containing g-mode pulsating components. A case study of KIC9850387
• Asteroseismic g-mode period spacings in strongly magnetic rotating stars
• The Traditional Approximation of Rotation including the centrifugal acceleration for slightly deformed stars
• Magnetic characterization of the SPB/$\beta$ Cep hybrid pulsator HD 43317
• Detecting deep axisymmetric toroidal magnetic fields in stars. The traditional approximation of rotation for differentially rotating deep spherical shells with a general azimuthal magnetic field
• The traditional approximation of rotation for rapidly rotating stars and planets. I. The impact of strong deformation
• Internal rotation and buoyancy travel time of 60 gamma Doradus stars from uninterrupted TESS light curves spanning 352 days
• Convection and Overshoot in models of gamma Doradus and delta Scuti stars
• A spectroscopic test of the rotational modulation origin of periodic \emph{Kepler} photometric variability of A-type stars
• Calibrating angular momentum transport in intermediate-mass stars from gravity-mode asteroseismology
• The traditional approximation of rotation for rapidly rotating stars and planets. II. Deformation and differential rotation
• Tidally perturbed g-mode pulsations in a sample of close eclipsing binaries
• Four bright eclipsing binaries with gamma Doradus pulsating components: CM Lac, MZ Lac, RX Dra and V2077 Cyg
• Multiscale entropy analysis of astronomical time series. Discovering subclusters of hybrid pulsators
• Exploring the convective core of the hybrid $\delta$ Scuti-$\gamma$ Doradus star CoRoT 100866999 with asteroseismology
• Constraining the near-core rotation of the gamma Doradus star 43 Cygni using BRITE-Constellation data
• Misclassified B stars in the Kepler field
• The ESO UVES/FEROS Large Programs of TESS OB pulsators. I. Global stellar parameters from high-resolution spectroscopy
• Physical properties of the eclipsing binary KIC 9851944 and analysis of its tidally-perturbed p- and g-mode pulsations
• In search of gravity mode signatures in main sequence solar-type stars observed by Kepler
• MOCKA -- A PLATO mock asteroseismic catalogue: Simulations for gravity-mode oscillators
• Distinguishing super-Nyquist frequencies via their temporal variation in $\gamma$ Doradus stars from continuous photometry
• Variable Blue Straggler Stars in Open Cluster NGC 6819 Observed in the Kepler 'Superstamp' Field
• Constraining differential rotation in gamma Doradus stars from inertial dips properties
• TIC441725813: A new bright hybrid sdB pulsator with differential core/envelope rotation
• Photometric and Spectroscopic Analysis of V583 Lyrae, an Algol with a g-mode Pulsating Primary and Accretion Disk
• Exploring the probing power of gamma-Dor's inertial dip for core magnetism: case of a toroidal field
• KIC 4150611: A quadruply eclipsing heptuple star system with a g-mode period-spacing pattern Asteroseismic modelling of the g-mode period-spacing pattern
• The effect of near-core mixing on rejuvenation and the asteroseismic properties of massive accretors
• OO Dra: an Algol-type binary formed through an extremely helium-poor mass accretion revealed by asteroseismology
• KIC 3868420: A high-amplitude $\delta$ Scuti-$\gamma$ Dor hybrid star crossing the Hertzsprung gap
• Isochrone-cloud fitting and asteroseismology of the Kepler open cluster NGC6866