J/ApJ/928/188 Seismic parameters of Kepler red giant stars (Dhanpal+, 2022)
Measuring frequency and period separations in red-giant stars using machine
learning.
Dhanpal S., Benomar O., Hanasoge S., Kundu A., Dhuri D., Das D., Kaul B.
<Astrophys. J., 928, 188 (2022)>
=2022ApJ...928..188D 2022ApJ...928..188D
ADC_Keywords: Asteroseismology; Stars, giant
Keywords: Asteroseismology ; Neural networks ; Red giant branch ;
Pulsation modes ; Stellar oscillations
Abstract:
Asteroseismology is used to infer the interior physics of stars. The
Kepler and TESS space missions have provided a vast data set of
red-giant lightcurves, which may be used for asteroseismic analysis.
These data sets are expected to significantly grow with future
missions such as PLATO, and efficient methods are therefore required
to analyze these data rapidly. Here, we describe a machine-learning
algorithm that identifies red giants from the raw oscillation spectra
and captures p- and mixed-mode parameters from the red-giant power
spectra. We report algorithmic inferences for large frequency
separation (Δν), frequency at maximum amplitude (νmax),
and period separation (ΔΠ) for an ensemble of stars. In
addition, we have discovered ∼25 new probable red giants among
151000 Kepler long-cadence stellar-oscillation spectra analyzed by
this method, among which four are binary candidates that appear to
possess red-giant counterparts. To validate the results of this
method, we selected ∼3000 Kepler stars, at various evolutionary stages
ranging from subgiants to red clumps, and compare inferences of
Δν, ΔΠ, and νmax with estimates obtained using
other techniques. The power of the machine-learning algorithm lies in
its speed: It is able to accurately extract seismic parameters from
1000 spectra in ∼5s on a modern computer (a single core of the
Intel(r) Xeon(r) Platinum 8280 CPU).
Description:
To construct the periodograms of Kepler data, we use the MAST data
from which we extract the PDCSAP lightcurves.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 53 25 List of new giant stars that were discovered
by machine
tablec2.dat 53 195 List of 195 red-giant stars detected in
Hon+ 2019, J/MNRAS/485/5616
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/A+A/525/A131 : Solar-like oscillations in Kepler red giants (Hekker+, 2011)
J/ApJ/749/152 : Asteroseismic analysis of solar-type stars (Mathur+, 2012)
J/A+A/540/A143 : Oscillations of Kepler red giants (Mosser+, 2012)
J/ApJ/765/L41 : Asteroseismic classification of KIC objects (Stello+, 2013)
J/ApJS/210/1 : Asteroseismic study of solar-type stars (Chaplin+, 2014)
J/A+A/572/L5 : Evolution of red giants from seismology (Mosser+, 2014)
J/ApJS/215/19 : APOKASC catalog of Kepler red giants (Pinsonneault+, 2014)
J/ApJ/827/50 : Kepler faint red giants (Mathur+, 2016)
J/A+A/588/A87 : Seismic global parameters of 6111 KIC (Vrard+, 2016)
J/A+A/600/A1 : Coupling factors of 5166 KIC (Mosser+, 2017)
J/A+A/598/A62 : KIC red giants showing depressed mixed modes (Mosser+, 2017)
J/A+A/616/A24 : Rotation in RGBs from Kepler asteroseismology (Gehan+, 2018)
J/A+A/618/A109 : Seismic global parameters of 372 KIC (Mosser+, 2018)
J/ApJS/239/32 : APOKASC-2 cat. of Kepler evolved stars (Pinsonneault+, 2018)
J/A+A/616/A94 : KIC red giants radial mode amplitudes (Vrard+, 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/485/5616 : Red giant solar-like oscillations in Kepler (Hon+, 2019)
J/A+A/639/A63 : Active red giants asteroseismic & rotation (Gaulme+, 2020)
J/MNRAS/493/1388 : Asteroseismology of Kepler luminous red giants (Yu+, 2020)
J/A+A/648/A113 : Kepler red giants in EBs RVs (Benbakoura+, 2021)
Byte-by-byte Description of file: tablec[12].dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/195] Running sequence number
5- 13 I09 --- KIC [1161491/100000928] KIC identifier (1)
15- 19 F5.2 uHz delnu [4.2/19] Frequency separation, Δν
21- 24 F4.2 uHz e_delnu [0.03/1.7] delnu uncertainty
26- 31 F6.2 s delpi [41.2/332.1] Period separation, ΔΠ
33- 38 F6.2 s e_delpi [0.8/207] delpi uncertainty
40- 46 F7.3 uHz numax [28.6/256.5] The p-mode frequency at maximum
power, νmax
48- 53 F6.3 uHz e_numax [0.026/18.4] numax uncertainty
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Note (1): Kepler ID 100000928 can be found on MAST
(http://archive.stsci.edu/kepler/data_search/search.php) but with
multiple coordinates (ranging from 19 20 53.853 +37 50 53.12 to
19 20 57.785 +37 51 00.56). It is not in the KIC target catalog.
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History:
From electronic version of the journal
Acknowledgements:
Siddharth Dhanpal [dhanpal.siddharth at gmail dot com]
(End) Emmanuelle Perret [CDS] 04-Mar-2024