J/A+A/616/A94 KIC red giants radial modes amplitude & lifetime (Vrard+, 2018)
Amplitude and lifetime of radial modes in red giant star spectra observed by
Kepler.
Vrard M., Kallinger T., Mosser B., Barban C., Baudin F., Belkacem K.,
Cunha M.S.
<Astron. Astrophys. 616, A94 (2018)>
=2018A&A...616A..94V 2018A&A...616A..94V (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Asteroseismology ; Spectroscopy
Keywords: asteroseismology - convection - stars: solar-type -
stars: evolution - stars: interiors - methods: data analysis
Abstract:
The space-borne missions CoRoT and Kepler have provided photometric
observations of unprecedented quality. The study of solar-like
oscillations observed in red giant stars by these satellites allows a
better understanding of the different physical processes occurring in
their interiors. In particular, the study of the mode excitation and
damping is a promising way to improve our understanding of stellar
physics that has, so far, been performed only on a limited number of
targets.
The recent asteroseismic characterization of the evolutionary status
for a large number of red giants allows us to study the physical
processes acting in the interior of red giants and how they are
modified during stellar evolution. In this work, we aim to obtain
information on the excitation and damping of pressure modes through
the measurement of the stars' pressure mode widths and amplitudes
and to analyze how they are modified with stellar evolution. The
objective is to bring observational constraints on the modeling of the
physical processes behind mode excitation and damping.
We fit the frequency spectra of red giants with well-defined
evolutionary status using Lorentzian functions to derive the pressure
mode widths and amplitudes. To strengthen our conclusions, we used two
different fitting techniques.
Pressure mode widths and amplitudes were determined for more than 5000
red giants. With a stellar sample two orders of magnitude larger than
previous results, we confirmed that the mode width depends on stellar
evolution and varies with stellar effective temperature. In addition,
we discovered that the mode width depends on stellar mass. We also
confirmed observationally the influence of the stellar metallicity on
the mode amplitudes, as predicted by models.
Description:
The two first data files contains the seismic global parameters of the
stars listed in the paper. Each star is identified with its KIC number
(Kepler Input Catalog).
The large separation are derived from the fit of the radial and
quadrupole oscillation modes. The frequency of maximum oscillation
power are derived from the autocorrelation of the oscillation spectra.
The global radial mode width are obtained from the mode widths of the
three radial modes closer to the frequency of maximum oscillation
power. The bolometric mode amplitude are derived from the mode
amplitude of the three radial mode with the highest mode amplitudes.
The radial mode widths and amplitudes are extracted from the
lorentzians fit that was performed on those modes. The stellar mass is
derived from the seismic scaling relations. The evolutionary status is
derived according to the method developped by Vrard et al.
(2016A&A...588A..87V 2016A&A...588A..87V, Cat. J/A+A/588/A87) and Kallinger et al.
(2012A&A...541A..51K 2012A&A...541A..51K)
The other files contain the raw data that was obtained from the radial
mode fitting. The mode frequencies, widths and amplitudes are derived
from lorentzians fit that was performed over the star radial modes
with the FREQ method.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
dataprob.dat 64 5523 Seismic global parameters and their error
bars extracted with the PROB method
datafreq.dat 64 5173 Seismic global parameters and their error
bars extracted with the FREQ method
fmp.dat 124 27373 *Radial mode parameters that was extracted with
the FREQ method for 5222 KIC
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Note on fmp.dat: For each KIC, each line correspond to a specific radial mode.
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/A+A/588/A87 : Seismic global parameters of 6111 KIC (Vrard+, 2016)
J/MNRAS/463/1297 : Asteroseismology of 1523 red giants (Yu+, 2016)
Byte-by-byte Description of file: dataprob.dat datafreq.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC KIC number
10- 14 F5.2 muHz Dnu Large separation
16- 20 F5.1 muHz numax Frequency of maximum oscillation power
22- 31 F10.3 muHz Gamma0 Global radial mode width at numax
33- 39 F7.4 muHz e_Gamma0 ?=-1 Uncertainty on Gamma0(numax)
41- 49 F9.2 ppm A0bol Bolometric mode amplitude
51- 55 F5.2 Msun M Mass in solar unit
57- 62 F6.3 Msun e_M ?=-1 Uncertainty in mass
64 I1 --- Status Evolutionary status (1)
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Note (1): Evolutionary status as follows:
1 = RGB
2 = red clump
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Byte-by-byte Description of file: fmp.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 I8 --- KIC KIC number
10- 15 F6.2 muHz nu Radial mode frequency
17- 33 F17.4 muHz e_nu ?=- Uncertainty on nu
35- 48 F14.4 muHz Gamma0 Mode width
50- 67 F18.4 muHz E_Gamma0 ?=- Upper uncertainty on Gamma0
68 A1 --- nEGamma0 [i] i for infinity
70- 82 F13.4 muHz e_Gamma0 ?=- Lower uncertainty on Gamma0
84- 92 F9.2 ppm A0 Mode amplitude
94-112 F19.3 ppm E_A0 ?=- Upper uncertainty on A0
113 A1 --- nEA0 [i] i for infinity
115-124 F10.3 ppm e_A0 ?=- Lower uncertainty on A0
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Acknowledgements:
Mathieu Vrard, mathieu.vrard(at)astro.up.pt
CAUP, Instituto de Astrofisica e Ciencias do Espaco
(End) Mathieu Vrard [CAUP], Patricia Vannier [CDS] 11-May-2018