J/MNRAS/490/4040 δ Scuti and γ Doradus stars in TESS (Antoci+, 2019)
The first view of δ Scuti and γ Doradus stars with the TESS mission.
Antoci V., Cunha M.S., Bowman D.M., Murphy S.J., Kurtz D.W., Bedding T.R.,
Borre C.C., Christophe S., Daszynska-Daszkiewicz J., Fox-Machado L.,
Garcia Hernandez A., Ghasemi H., Handberg R., Hansen H., Hasanzadeh A.,
Houdek G., Johnston C., Justesen A.B., Kahraman Alicavus F., Kotysz K.,
Latham D., Matthews J.M., Monster J., Niemczura E., Paunzen E.,
Sanchez Arias J.P., Pigulski A., Pepper J., Richey-Yowell T., Safari H.,
Seager S., Smalley B., Shutt T., Sodor A., Suarez J.-C., Tkachenko A.,
Wu T., Zwintz K., Barcelo Forteza S., Brunsden E., Bognar Z., Buzasi D.L.,
Chowdhury S., De Cat P., Evans J.A., Guo Z., Guzik J.A., Jevtic N.,
Lampens P., Lares Martiz M., Lovekin C., Li G., Mirouh G.M., Mkrtichian D.,
Monteiro M.J.P.F.G., Nemec J.M., Ouazzani R.-M., Pascual-Granado J.,
Reese D.R., Rieutord M., Rodon J.R., Skarka M., Sowicka P., Stateva I.,
Szabo R., Weiss W.W.
<Mon. Not. R. Astron. Soc., 490, 4040-4059 (2019)>
=2019MNRAS.490.4040A 2019MNRAS.490.4040A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, A-type ; Stars, F-type ; Stars, variable ;
Asteroseismology ; Effective temperatures ; Optical ;
Rotational velocities
Keywords: asteroseismology - techniques: photometric -
stars: chemically peculiar - stars: interiors -
stars: variables: δ Scuti
Abstract:
We present the first asteroseismic results for δ Scuti and
γ Doradus stars observed in Sectors 1 and 2 of the TESS mission.
We utilize the 2-min cadence TESS data for a sample of 117 stars to
classify their behaviour regarding variability and place them in the
Hertzsprung-Russell diagram using Gaia DR2 data. Included within our
sample are the eponymous members of two pulsator classes,
γ Doradus and SX Phoenicis. Our sample of pulsating
intermediate-mass stars observed by TESS also allows us to confront
theoretical models of pulsation driving in the classical instability
strip for the first time and show that mixing processes in the outer
envelope play an important role. We derive an empirical estimate of 74
per cent for the relative amplitude suppression factor as a result of
the redder TESS passband compared to the Kepler mission using a
pulsating eclipsing binary system. Furthermore, our sample contains
many high-frequency pulsators, allowing us to probe the frequency
variability of hot young δ Scuti stars, which were lacking in
the Kepler mission data set, and identify promising targets for future
asteroseismic modelling. The TESS data also allow us to refine the
stellar parameters of SX Phoenicis, which is believed to be a blue
straggler.
Description:
The TESS data analysed in this work are the 2-min 'Simple Aperture
Photometry' (SAP) light curves provided by the TESS Science Team,
which are publicly available from the Mikulski Archive for Space
Telescopes (MAST) (https://archive.stsci.edu). As part of the
framework of the asteroseismic working group on pulsating stars of
spectral type A and F within the TESS Asteroseismic Science Consortium
(TASC, https://tasoc.dk), 117 known pulsating stars were allocated
observing slots at a 2-min cadence by the TESS Mission in Sectors 1
and 2 of its 1-yr observing campaign in the southern ecliptic
hemisphere. There were more δ Sct stars observed in the first
two sectors, but for this study we decided to concentrate on those
that were allocated to the TASC working group on A and F stars (TASC
WG 4). Because g modes have long periods, we did not specifically
include known γ Dor stars in our 2-min target list, since these
stars will be observed with a cadence of 30min, which is sufficient to
determine their frequencies.
Spectroscopic and photometric parameters from the literature for all
the stars, where available, are assembled in Table A1, including
claimed detections of binarity. In Table A2, we list the newly derived
effective temperatures using the spectral energy distribution method
(SED), new spectroscopically derived parameters, the dereddened
luminosities from Gaia and Hipparcos data, and the TESS stellar
variability type.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 113 117 Stellar parameters for the TESS δ Sct and
γ Dor pulsators observed at 2-min cadence
during the first two pointings in the ecliptic
Southern hemisphere
tablea2.dat 117 117 Stellar parameters and variability type of the
2-min cadence TESS δ Scuti and γ Dor
pulsators determined in this work
refs.dat 71 48 References for Table A1
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See also:
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- TIC [9632550/469933721] TESS Input Catalog (TIC)
number
11- 15 F5.2 mag TESSmag TESS magnitude
17- 39 A23 --- Name Star name
41- 44 I4 K Teffsp ? Spectroscopic effective temperature
46- 47 I2 --- r_Teffsp ? Reference for Teffsp in refs.dat file
49- 51 I3 K e_Teffsp ? Error on Teffsp
53- 57 I5 K Teffph ? Photometric effective temperature
59- 60 I2 --- r_Teffph ? Reference for Teffph in refs.dat file
62- 64 I3 K e_Teffph ? Error on Teffph
66- 69 F4.2 [cm/s2] loggsp ? Spectroscopic surface gravity
71- 72 I2 --- r_loggsp ? Reference for loggsp in refs.dat file
74- 77 F4.2 [cm/s2] e_loggsp ? Error on loggsp
79- 83 F5.3 [cm/s2] loggph ? Photometric surface gravity
85- 86 I2 --- r_loggph ? Reference for loggph in refs.dat file
88- 91 F4.2 [cm/s2] e_loggph ? Error on loggph
93- 97 F5.1 km/s vsini ? Projected rotational velocity
99-100 I2 --- r_vsini ? Reference for vsini in refs.dat file
102-103 I2 km/s e_vsini ? Error on vsini
105-110 A6 --- binary Binarity status
112-113 I2 --- r_binary ? Reference for binary in refs.dat file
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Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- TIC [9632550/469933721] TESS Input Catalog (TIC)
number
11- 33 A23 --- Name Star name
35- 39 I5 K Teff ? Effective temperature derived using the
SED method
41- 43 I3 K e_Teff ? Error on Teff
45- 49 F5.3 [Lsun] logLg ? Logarithm of the stellar luminosity
derived using gaia parallaxes
51- 55 F5.3 [Lsun] e_logLg ? Error on logLg
57- 60 F4.2 [Lsun] logLH ? Logarithm of the stellar luminosity
derived using Hipparcos parallaxes
62- 65 F4.2 [Lsun] e_logLH ? Error on logLH
67-114 A48 --- Vartype Variability type derived from the TESS
data (1)
116-117 A2 --- chempec [Am] Chemical peculiarity as described in
Renson & Manfroid (2009A&A...498..961R 2009A&A...498..961R,
Cat. III/260)
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Note (1): The variability type can be: δ Sct: ν≥4d-1;
γ Dor: ν=<4d-1; hybrid: when frequencies were detected in
the γ Dor and the δ Sct frequency ranges ;
binarity: eclipses and/or ellipsoidal modulation were detected;
rotational variable (rot): variability is consistent with rotational
modulation of spotted stellar surfaces; no detection: no significant
variability was detected.
Finally, the question mark means that the variability type is
uncertain (e.g. due to unresolved peaks) and HAGD denotes a
High-Amplitude γ Dor star.
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Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Ref [1/52] Reference number
4- 22 A19 --- BibCode BibCode
24- 49 A26 --- Aut Author's name
51- 71 A21 --- Com Comments
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 01-Feb-2023