J/A+A/690/A104 Catalogue of Am/Fm Variability (Durfeldt-Pedros+, 2024)
Variability and stellar pulsation incidence in Am and Fm stars using TESS and
Gaia data.
Durfeldt-Pedros O., Antoci V., Smalley B., Murphy S., Posilek N.,
Niemczura E.
<Astron. Astrophys. 690, A104 (2024)>
=2024A&A...690A.104D 2024A&A...690A.104D (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Stars, Am ; Stars, F-type ; Photometry ;
Optical ; Effective temperatures
Keywords: stars: chemically peculiar - stars: oscillations -
stars: variables: delta Scuti - stars: variables: general
Abstract:
We aim to study chemically peculiar Am and Fm stars, distinguished by
their unique abundance patterns, which are crucial for studying mixing
processes in intermediate-mass stars. These stars provide a window
into the atomic diffusion in their stellar envelopes, the
evolution-dependent changes in mixing, and the resulting effects on
pulsation mechanisms.
This study examines the pulsation characteristics of the Am and Fm
star group. Our analysis encompasses 1276 stars (available as
catalogues on GitHub), utilising data from TESS and Gaia and focussing
on stars from the Renson catalogue.
In our sample, 51% of stars (649) display no variability, and are thus
categorised as constant stars. Among those that remain, 25% (318
stars) are pulsating Am, Fm, and ρ Puppis stars, including 20%
(261 stars) that are exclusively Am and Fm stars. Additionally, 17% of
stars (210) show variability indicative of binarity and/or rotational
modulation and 7% (93 stars) are eclipsing binaries. Of the pulsating
stars, 10% (32 stars) are γ Doradus type, 54% (172 stars)
δ Scuti type, and 36% (114 stars) are hybrids, underlining a
diverse pulsational behaviour of Am and Fm stars.
Our findings indicate that pulsating stars predominantly occupy
positions near the red edge of the classical instability strip,
allowing us to ascertain the incidence of pulsations in this stellar
population.
Description:
We present the results of a study of stellar oscillations in 1276
chemically peculiar Am and Fm stars. We classified the stellar
variability and performed a frequency analysis of pulsating stars,
deriving the frequency range of g- and p-modes. For p mode hosting
stars, the number of excited radial orders were determined. The
results show a diverse pulsational behaviour in Am and Fm stars, with
25% of the sample hosting stellar oscillations. We found 32 Gamma
Doradus stars, 172 Delta Scuti stars, and 114 hybrid stars with both
g- and p modes. Additionally, 93 eclipsing binaries and 108 stars with
other variability, either due to modulation or ellipsoidal variability
were identified. Radial order excitation is dominant near the main
sequence, extending along two ridges towards later stages of
evolution, which may suggest several pulsation mechanism are at play.
TESS light curves were obtained for each star over the span of 58
sectors for the variability classification. Computation of
Lomb-Scargle periodograms allowed for frequency extraction and
identification of combination frequencies, which were ignored in the
analysis of excited radial orders and ranges of pulsation frequencies.
Gaia DR3 stellar parameters were obtained to place the stars in HR
diagrams and predict the frequency of successive radial orders of p
modes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 158 1276 Am and Fm stars variability summary table
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See also:
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq [0/1275] Table index
6- 15 I10 --- TIC TESS identifier
17- 35 I19 --- GaiaDR3 Gaia DR3 identifier
37- 50 A14 --- Name Alternative identifier, typically the HD
identifier unless unique names are found
52- 58 F7.3 deg RAdeg Right ascension (J2000.0)
60- 66 F7.3 deg DEdeg Declination (J2000.0)
68- 72 I5 K Teff Effective temperature
74- 76 F3.1 [cm/s2] logg Surface gravity
78- 83 F6.1 Lsun L Luminosity
85- 89 F5.1 Lsun e_L Luminosity error
91- 97 F7.3 --- Vmag V-band magnitude
99-110 A12 --- VarClass Variability classification (1)
112-122 A11 1/d gmodeRange Frequency range of g modes
124-136 A13 1/d pmodeRange Frequency range of p modes
138 I1 --- Norders ?=- Number of excited radial orders (2)
140-151 A12 --- Binary Binary type (3)
153-154 I2 --- Nsectors Number of TESS sectors
156-158 A3 --- RhoPuppis Rho Puppis flag, 'Yes' or -
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Note (1): Variability classification as follows:
DS = Delta Scuti
GD = Gamma Doradus
HY = hybrid
EB = eclipsing binary
OV = other variability
- = not variable
Note (2): From 0 to 9 for stars hosing p modes, all other stars are
assigned a dash: -
Note (3): Binary type as follows:
EB = eclipsing binary
Known = known binary from literature
- = not a binary
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Acknowledgements:
Oliver Doerfeldt Pedros, durfeldtpedros.o(at)gmail.com
(End) Patricia Vannier [CDS] 27-Aug-2024