J/A+A/706/L5 Seismic global parameters of 41 KIC (Mosser+, 2026)
Extra modes in helium-core-burning stars probing an infra core cavity.
Mosser B., Takata M., Pincon C., Cunha M.S., Vrard M., Belkacem K.,
Deheuvels S., Matteuzzi M.
<Astron. Astrophys. 706, L5 (2026)>
=2026A&A...706L...5M 2026A&A...706L...5M (SIMBAD/NED BibCode)
ADC_Keywords: Associations, stellar ; Asteroseismology ; Optical
Keywords: stars: evolution - stars: fundamental parameters -
stars: horizontal-branch - stars: interiors - stars: oscillations
Abstract:
Dipole mixed modes observed in the oscillation pattern of red giant
stars probe the radiative regions in the stellar core.
Oscillation spectra of helium-core-burning stars sometimes show extra
peaks that remain unexplained by the dipole mixed-mode pattern
expected from the coupling of a radiative cavity in the stellar core
and a pressure cavity in the stellar envelope.
We use the asymptotic expansion developed for a multi-cavity star in
order to characterize these extra peaks.
The analytical resonance condition of the multi-cavity
gravito-acoustic modes, with two inner gravity cavities and an outer
pressure cavity, helps us explain that the apparent extra peaks are
dipole mixed modes that follow the three-cavity oscillation pattern.
The derivation of the two asymptotic period spacings associated with
the two distinct regions in the radiative core provides an estimate of
the full radiative cavity.
Our results provide new constraints for analyzing the overshoot or
mixing in the core of helium-core-burning stars. An important
structure discontinuity inside the radiative core may explain the
larger than expected observed period spacings.
Description:
Period spacings of the red-clump stars analyzed in the paper. Each
star is identified with its KIC number (Kepler Input Catalog).
Estimates of the large separation are derived from Mosser &
Appourchaux (2009A&A...508..877M 2009A&A...508..877M). Estimates of the period spacings
and evolutionary stages are based on the 3-cavity formalism of Pincon
& Takata (2022A&A...661A.139P 2022A&A...661A.139P).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 38 41 Seismic global parameters
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
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 KIC number
9- 13 F5.2 muHz Dnu Large separation
14- 19 F6.3 --- q Coupling factor between p- and g-cavity
20- 25 F6.1 s DPi1o Period spacing of the outer g-cavity
26- 31 F6.3 --- qg Coupling factor between the g-cavities
32- 38 F7.1 s DPi1i Period spacing of the inner g-cavity
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Acknowledgements:
Benoit Mosser, benoit.mosser(at)observatoiredeparis.psl.eu
(End) Patricia Vannier [CDS] 09-Jan-2026