J/A+A/693/A63 Distinguishing SNFs via their temporal variation (Xuan+, 2025)
Distinguishing super-Nyquist frequencies via their temporal variation in
gamma Doradus stars from continuous photometry.
Wang X., Zong W., Ma X.-Y., Charpinet C., Wu T., Wang H.
<Astron. Astrophys. 693, A63 (2025)>
=2025A&A...693A..63W 2025A&A...693A..63W (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Asteroseismology ; Optical
Keywords: methods: statistical - technique: photometric -stars: oscillations
Abstract:
As mixed with real pulsations, the reflection of super-Nyquist
frequencies (SNFs) pose a threat to asteroseismic properties. Although
SNFs have been studied in several pulsating stars, a systematic survey
remains scarcely to be explored. Here we propose a method to identify
SNFs from Kepler and TESS photometry by characterizing their periodic
frequency modulations using a sliding Fourier transform. After
analyzing long cadence photometry in the Kepler legacy, we have
identified 304 SNFs in 56 stars from 45607 frequencies in ∼600 γ
Doradus stars, corresponding to a fraction of approximately 0.67% and
9.2%, respectively. Most SNFs are detected in the frequency range of
pressure mode over 120µHz and the fraction of SNF detection
increases as frequency up to ∼7%. We barely found two potential SNFs
mixed with gravity modes in two γ Doradus stars. These findings
indicate that SNFs have a negligible impact on global seismic
properties, such as those derived from period spacing in γ
Doradus stars. However, we stress that SNFs must be carefully and
systematically examined by this method in other pulsating stars,
particularly δ Scuti and hot B subdwarf stars, to establish a
solid foundation for precise asteroseismolgy of various types of
pulsators.
Description:
The 304 SNFs identified in 56 γ Dor stars after thoroughly
examining the sliding LSP for all relevant frequencies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 61 304 All 304 identified SNFs in 56 gamma Dor stars
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC KIC identifier
13- 21 F9.5 uHz fdetect Super-Nyquist frequency
26- 32 F7.5 uHz e_fdetect Super-Nyquist frequency error
36- 41 F6.1 ppm Amp Amplitude of the super-Nyquist frequency
45- 48 F4.1 ppm e_Amp Amplitude error of the super-Nyquist frequency
53- 61 F9.5 uHz freal Real frequency corresponding to the
super-Nyquist frequency
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Acknowledgements:
Xaun Wang, wang.xuan(at)mail.bnu.edu.cn
Weikai Zong, weikai.zong(at)bnu.edu.cn
(End) Xuan Wang [BNU], Patricia Vannier [CDS] 22-Nov-2024