J/ApJ/954/152 Low-luminosity Kepler red giants analysis (Kuszlewicz+, 2023)
Mixed-mode ensemble asteroseismology of low-luminosity Kepler red giants.
Kuszlewicz J.S., Hon M., Huber D.
<Astrophys. J., 954, 152 (2023)>
=2023ApJ...954..152K 2023ApJ...954..152K
ADC_Keywords: Asteroseismology; Stars, giant; Stars, masses; Abundances
Keywords: Asteroseismology ; Stellar properties ; Stellar oscillations ;
Astronomy data analysis
Abstract:
We present measurements of the dipole mode asymptotic period spacing
(ΔΠ1), the coupling factor between the p- and g-modes (q),
the g-mode phase offset (εg), and the mixed-mode frequency
rotational splitting (δνrot) for 1074 low-luminosity red
giants from the Kepler mission. Using oscillation mode frequencies
extracted from each star, we apply Bayesian optimization to estimate
ΔΠ1 from the power spectrum of the stretched-period spectrum
and to perform the subsequent forward modeling of the mixed-mode
frequencies. With our measurements, we show that the mode coupling
factor q shows significant anticorrelation with both the stellar mass
and metallicity, and can reveal highly metal-poor stars. We present
the evolution of εg up the lower giant branch up to before the
luminosity bump, and find no significant trends in εg or
δνrot with the stellar mass and metallicity in our sample.
Additionally, we identify six new red giants showing anomalous
distortions in their g-mode pattern.
Description:
For our analysis in this study, we extract the mixed-mode parameters
of 1183 stars analyzed in the work by Gehan+ (2018, J/A+A/616/A24),
which is a sample sufficiently representative of low-luminosity red
giants within the Kepler mission. We also used light curves from the
KEPSEISMIC database (Mathur+ 2019, doi:10.17909/t9-mrpw-gc07).
We successfully peak bagged 1140 red giants from the initial sample of
1183. From these 1140 stars, we found 1068 whose best (ΔΠ1,
q, εg , δνrot) BayesOpt solution yield a forward
model that fits the observed mixed-mode pattern with and produces
meaningful clusters in the 4D parameter space.
The data products from our analysis, which include the global seismic
parameters, background-corrected power spectra, list of detected
frequencies, and l=0,2 mode identifications for each red giant are
made openly available at doi:10.5281/zenodo.7888633
See Section 2.5.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 102 1068 Mixed-mode parameters of 1068 Kepler red giants
from the Gehan+ 2018, J/A+A/616/A24 sample
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
III/286 : APOGEE-2 DR17 final allStar catalog (Abdurro'uf+, 2022)
J/A+A/540/A143 : Oscillations of red giants with Kepler (Mosser+, 2012)
J/ApJ/765/L41 : Asteroseismic classification of KIC objects (Stello+, 2013)
J/A+A/572/L5 : Evol. state of red giants from seismology (Mosser+, 2014)
J/A+A/588/A87 : Seismic global parameters of 6111 KIC (Vrard+, 2016)
J/MNRAS/466/3344 : Red-giant stars classification (Elsworth+, 2017)
J/MNRAS/469/4578 : Deep learning classif. in asteroseismology (Hon+, 2017)
J/A+A/600/A1 : Coupling factors of 5166 KIC (Mosser+, 2017)
J/A+A/616/A24 : Rotation in RGBs from Kepler asteroseismology (Gehan+, 2018)
J/MNRAS/476/3233 : 14983 Kepler red giants (Hon+, 2018)
J/A+A/618/A109 : Seismic global parameters of 372 KIC (Mosser+, 2018)
J/ApJS/236/42 : Asteroseismology of ∼16000 Kepler red giants (Yu+, 2018)
J/MNRAS/489/4641 : APOKASC Evol. state of red-giant stars (Elsworth+, 2019)
J/MNRAS/488/572 : Bayesian hierarchical inclinations (Kuszlewicz+, 2019)
J/ApJ/887/203 : Core rot. period measurements of KIC stars (Tayar+, 2019)
J/A+A/645/A124 : Inclinations for RGBs from Kepler (Gehan+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC [1027337/12885196] Kepler Input Catalog
identifier
10- 16 F7.3 s DPi1 [61.9/102.3] Asymptotic dipole mode period
spacing
18- 22 F5.3 s e_DPi1 [0/3.7] Asymptotic dipole mode period spacing
lower interval
24- 28 F5.3 s E_DPi1 [0/3.5] Asymptotic dipole mode period spacing
upper interval
30- 34 F5.3 --- q [0.059/0.3] Mixed-mode coupling factor
36- 40 F5.3 --- e_q [0/0.2] Mixed-mode coupling factor lower interval
42- 46 F5.3 --- E_q [0/0.21] Mixed-mode coupling factor upper
interval
48- 53 F6.3 --- eps-g [-0.5/0.5] g mode phase offset (1)
55- 59 F5.3 --- e_eps-g [0/0.71] g mode phase offset lower interval
61- 65 F5.3 --- E_eps-g [0/0.81] g mode phase offset upper interval
67- 71 F5.3 uHz drot [0/0.93] Mixed-mode rotational splitting
73- 77 F5.3 uHz e_drot [0/0.4] Mixed-mode rotational splitting lower
interval
79- 83 F5.3 uHz E_drot [0/0.5] Mixed-mode rotational splitting upper
interval
85- 90 F6.3 [-] [M/H] [-1.15/0.44]? Metallicity (2)
92- 96 F5.3 Msun Mass [0.85/1.89]? Mass
98- 102 F5.3 Msun e_Mass [0.05/0.13]? Mass uncertainty
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Note (1): Reported values are offset by -0.5 for consistency with
previous literature convention
Note (2): Measurements adopted from APOGEE DR17 (see III/286)
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History:
From electronic version of the journal
Licences: cc-by
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 07-Oct-2025