J/A+A/688/A93 Sample of ∼60000 OBAF-type pulsators (Hey+, 2024)
Confronting sparse Gaia DR3 photometry with TESS for a sample of
around 60000 OBAF-type pulsators.
Hey D., Aerts C.
<Astron. Astrophys. 688, A93 (2024)>
=2024A&A...688A..93H 2024A&A...688A..93H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Optical
Keywords: stars: general - stars: oscillations - stars: variables: delta Scuti -
stars: variables: general
Abstract:
The Gaia mission has delivered hundreds of thousands of variable star
light curves in multiple wavelengths. Recent work demonstrates that
these light curves can be used to identify (non-)radial pulsations in
OBAF-type stars, despite their irregular cadence and low light curve
precision, of the order of a few millimagnitudes. With the
considerably more precise TESS photometry, we revisited these
candidate pulsators to conclusively ascertain the nature of their
variability.
We seek to re-classify the Gaia light curves with the first two years
of TESS photometry for a sample of 58970 p- and g-mode pulsators,
encompassing gamma Dor, delta Scuti, slowly pulsating B, and beta Cep
variables. From the TESS data, we seek to assess the quality of
Gaia's classification of non-radial pulsators, which is based on
sparse, years-long light curves of millimagnitude precision. We also
supply four new catalogues containing the confirmed pulsators, along
with their dominant and secondary pulsation frequencies, the number of
independent mode frequencies, and a ranking according to their
usefulness for future asteroseismic ensemble analysis.
We first analysed the TESS light curves independent of their Gaia
classification by pre-whitening all dominant pulsation modes down to a
1% false alarm probability. Using this, in combination with a
feature-based random forest classifier, we identified different
variability types across the sample.
We find that the Gaia photometry is exceptionally accurate for
detecting the dominant and secondary frequencies, reaching
approximately 80% accuracy in frequency for p- and g-mode pulsators.
The majority of Gaia classifications are consistent with the
classifications from the TESS data, illustrating the power of the
low-cadence Gaia photometry for pulsation studies. We find that the
sample of g-mode pulsators forms a continuous group of variable stars
along the main sequence across B, A, and F spectral types, implying
that the mode excitation mechanisms for all these pulsators need to be
updated with improved physics. Finally, we provide a rank-ordered
table of pulsators according to their asteroseismic potential for
follow-up studies, based on the number of sectors they have been
observed in, their classification probability, and the number of
independent modes found in the TESS light curves from the nominal
mission.
Our catalogue offers a major increase in the number of confirmed
g-mode pulsators with an identified dominant mode suitable for
follow-up TESS ensemble asteroseismology of such stars.
Description:
We have examined the pulsators of spectral type O, B, A, or F
classified from Gaia DR3 photometry by Gaia Collaboration et al.
(2022A&A...668A.137G 2022A&A...668A.137G) and having TESS high-cadence light curves.
For each candidate variable from Gaia, we find that the majority of
their TESS light curve classifications are in good agreement with
their Gaia classification. These results point to around 6000 new
γ Dor, 20000 new δ Scuti, and 1481 new SPB pulsators
confirmed by TESS.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 93622 Classifications of the p- and g-mode candidate
sample
table3.dat 214 58970 Rank ordered tables for the gamma Dor,
delta Scuti, and SPB, and beta Cep
classified pulsators
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Gaia DR3 source id
21- 22 I2 --- Sector [1/26] The sector of observation
24- 31 A8 --- Pred Predicted class
33- 36 F4.2 --- PCONTACT Probability of CONTACT class
38- 41 F4.2 --- PDSCT Probability of DSCT class
43- 46 F4.2 --- PEB Probability of EB class
48- 51 F4.2 --- PGDOR/SPB Probability of GDOR/SPB class
53- 56 F4.2 --- PHYBRID Probability of HYBRID class
58- 61 F4.2 --- PROT Probability of ROT class
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR2 Gaia DR2 source id
21- 39 I19 --- GaiaDR3 Gaia DR3 source id
41- 50 I10 --- TIC TESS Input Catalog source id
52- 55 F4.1 --- Npeaks ? Number of peaks present in
amplitude spectrum
57- 60 A4 --- Sample The origin of the sample
62- 69 A8 --- Pred The predicted class
71- 88 F18.16 --- Predproba ? The predicted class probability
90-108 F19.16 d-1 f1TESS ? Dominant frequency
110-128 F19.16 d-1 f2TESS ? Secondary frequency
130-150 F21.16 10-3 A1TESS ? Dominant amplitude (ppt unit)
152-172 F21.16 10-3 A2TESS ? Secondary amplitude (ppt unit)
174-192 F19.16 d-1 meanFreq ? Mean frequency
194-195 I2 --- Sector Number of TESS sectors of observation
197-214 F18.16 --- Ranking ? Asteroseismic ranking
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Acknowledgements:
Daniel Hey, danielhey(at)outlook.com
(End) Patricia Vannier [CDS] 28-Jun-2024