Distinguishing SNFs via their temporal variation

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 {gamma} 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 120{mu}Hz and the fraction of SNF detection increases as frequency up to ~7%. We barely found two potential SNFs mixed with gravity modes in two {gamma} Doradus stars. These findings indicate that SNFs have a negligible impact on global seismic properties, such as those derived from period spacing in {gamma} Doradus stars. However, we stress that SNFs must be carefully and systematically examined by this method in other pulsating stars, particularly {delta} Scuti and hot B subdwarf stars, to establish a solid foundation for precise asteroseismolgy of various types of pulsators.

Cone search capability for table J/A+A/693/A63/table2 (All 304 identified SNFs in 56 gamma Dor stars)

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/A+A/693/A63
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/693/A63
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/693/A63
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/A+A/693/A63
Provenance
Creator Wang X.; Zong W.; Ma X.-Y.; Charpinet C.; Wu T.; Wang H.
Publisher CDS
Publication Year 2025
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy