J/A+A/688/A25 Classification of A-F spectral type stars (Skarka+, 2024)
Periodic variable A-F spectral type stars in the southern TESS continuous
viewing zone. I. Identification and classification.
Skarka M., Henzl Z.
<Astron. Astrophys. 688, A25 (2024)>
=2024A&A...688A..25S 2024A&A...688A..25S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Stars, F-type; Stars, A-type
Keywords: methods: data analysis - catalogs - stars: oscillations -
stars: rotation - stars: variables: general
Abstract:
Our primary objective is to accurately identify and classify the
variability of A-F stars in the southern continuous viewing zone
of the TESS satellite. The brightness limit was set to 10 mag to
ensure the utmost reliability of our results and allow for
spectroscopic follow-up observations using small telescopes. We aim to
compare our findings with existing catalogues of variable stars.
The light curves from TESS and their Fourier transform were used to
manually classify stars in our sample. Cross-matching with other
catalogues was performed to identify contaminants and false positives
We have identified 1171 variable stars (51% of the sample). Among
these variable stars, 67% have clear classifications, which includes
δ Sct and γ Dor pulsating stars and their hybrids,
rotationally variables, and eclipsing binaries. We have provided
examples of the typical representatives of variable stars and
discussed the ambiguous cases. We found 20 pairs of stars with the
same frequencies and identified the correct source of the variations.
Additionally, we found that the variations in 12 other stars are
caused by the contamination with the light of faint nearby
large-amplitude variable stars. To compare our sample with other
variable star catalogues, we have defined two parameters reflecting
the agreement in identification of variable stars and their
classification. This comparison reveals intriguing disagreements in
classification ranging from 52% to 100 %. However, if we assume that
stars without specific types are only marked as variable, then the
agreement is relatively good, ranging from 57% to 85% (disagreement
15-43%). We have demonstrated that the TESS classification is superior
to the classification based on other photometric surveys.
The classification of stellar variability is complex and requires
careful consideration. Caution should be exercised when using
catalogue classifications.
Description:
We present a classification of A-F spectral type stars brighter than
10 mag that are located in the southern TESS continuous viewing zone.
We found clear signs of variability in 1171 of 2302 studied stars
(51%). For 67% of the classified stars we were able to estimate the
variability type.
The classification is based on the light-curve shape and Fourier
transform of photometric data investigated manually. We used TESS SPOC
and QLP data products. For ech star we give identification in the TIC
catalogue, equatorial coordinates, contamination ratio, number of
stars that are closer than 5 pixels having brightness difference less
than 5mag, variability type, brightness in V, effective temperature,
and luminosity.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 86 2302 Classification of A-F spectral type stars in the
southern TESS viewing zone
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See also:
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 I9 ---- Name Number in the TIC catalogue
11- 25 F15.11 deg RAdeg Right ascension (J2000) (1)
27- 41 F15.11 deg DEdeg Declination (J2000) (1)
43- 49 F7.4 ---- CR ? Contamination ratio (2)
51- 52 I2 ---- Blends Number of blending stars with brightness
difference less than 5mag
55- 68 A14 ---- Type Variability type
71- 75 F5.2 mag Vmag Brightness in V (1)
77- 80 I4 K Teff Effective temperature (1)
82- 86 F5.1 Lsun Lum ? Luminosity (1)
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Note (1): Values from Stassun et al., 2019AJ....158..138S 2019AJ....158..138S, Cat. IV/38
Note (2): Values from Paegert et al., 2021arXiv210804778P 2021arXiv210804778P
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Acknowledgements:
Marek Skarka, skarka(at)asu.cas.cz
(End) Patricia Vannier [CDS] 01-Jul-2024