J/ApJS/253/11 TESS observations of Cepheid stars (Plachy+, 2021)
TESS observations of Cepheid stars: first light results.
Plachy E., Pal A., Bodi A., Szabo P., Molnar L., Szabados L., Benko J.M.,
Anderson R.I., Bellinger E.P., Bhardwaj A., Ebadi M., Gazeas K.,
Hambsch F.-J., Hasanzadeh A., Jurkovic M.I., Kalaee M.J., Kervella P.,
Kolenberg K., Mikolajczyk P., Nardetto N., Nemec J.M., Netzel H.,
Ngeow C.-C., Ozuyar D., Pascual-granado J., Pilecki B., Ripepi V.,
Skarka M., Smolec R., Sodor A., Szabo R., Christensen-Dalsgaard J.,
Jenkins J.M., Kjeldsen H., Ricker G.R., Vanderspek R.
<Astrophys. J. Suppl. Ser., 253, 11-11 (2021)>
=2021ApJS..253...11P 2021ApJS..253...11P (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable; Photometry; Optical
Keywords: Stellar pulsations; Cepheid variable stars; Stellar photometry
Abstract:
We present the first analysis of Cepheid stars observed by the TESS
space mission in Sectors 1-5. Our sample consists of 25 pulsators: ten
fundamental mode, three overtone and two double-mode classical
Cepheids, plus three type II and seven anomalous Cepheids. The targets
were chosen from fields with different stellar densities, both from
the Galactic field and from the Magellanic System. Three targets have
2 minutes cadence light curves available by the TESS Science
Processing Operations Center: for the rest, we prepared custom light
curves from the full-frame images with our own differential
photometric FITSH pipeline. Our main goal was to explore the potential
and the limitations of TESS concerning the various subtypes of
Cepheids. We detected many low-amplitude features: weak modulation,
period jitter, and timing variations due to light-time effect. We also
report signs of nonradial modes and the first discovery of such a mode
in an anomalous Cepheid, the overtone star XZ Cet, which we then
confirmed with ground-based multicolor photometric measurements. We
prepared a custom photometric solution to minimize saturation effects
in the bright fundamental-mode classical Cepheid, β Dor with the
lightkurve software, and we revealed strong evidence of cycle-to-cycle
variations in the star. In several cases, however, fluctuations in the
pulsation could not be distinguished from instrumental effects, such
as contamination from nearby sources, which also varies between sectors.
Description:
The NASA Transiting Exoplanet Survey Satellite (TESS) observations
consist of ∼27 day long measurements with constant pointing to a
24°x96° field of view, called a "sector". In this paper, we
present the first results on Cepheid stars observed with TESS,
covering the first five out of 26 sectors of its primary 2yr near
all-sky mission (2018-2019).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 111 26 Targets
table8.dat 75 69574 *The FITSH photometry prepared for 23 full-frame
image target stars analysed
table9.dat 54 88634 The 2-minute cadence custom aperture photometry
prepared for Β Dor
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Note on table8.dat: To produce light curves from the full-frame images (FFIs)
we used the FITSH package developed by Pal (2012MNRAS.421.1825P 2012MNRAS.421.1825P).
See Section 2.
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/AJ/108/222 : Pop. II variable stars (Nemec+, 1994)
J/A+A/312/111 : [Fe/H] from RR Lyrae light curves (Jurcsik+, 1996)
J/A+A/381/32 : Galactic Cepheid abundances (Andrievsky+, 2002)
J/A+A/442/381 : Precise positions of RR Lyrae with Vmax>12.5 (Maintz, 2005)
J/A+A/453/309 : HARPS observations of nine galactic Cepheids (Nardetto+, 2006)
J/A+A/461/613 : The anomalous Cepheid XZ Ceti (Szabados+, 2007)
J/ApJ/683/433 : Polaris monitoring (Bruntt+, 2008)
J/AcA/58/163 : VI light curves of LMC classical Cepheids (Soszynski+, 2008)
J/AcA/58/293 : Type-II and anomalous Cepheids in LMC (Soszynski+, 2008)
J/ApJ/715/277 : Insights into the Cepheid distance scale (Bono+, 2010)
J/AcA/60/91 : VI light curves of SMC type II Cepheids (Soszynski+, 2010)
J/MNRAS/413/2709 : BVRI light curves of KIC Cepheids (Szabo+, 2011)
J/MNRAS/436/953 : OGLE-LMC-CEP-0227 RV and VI[3.6] curves (Pilecki+, 2013)
J/MNRAS/437/2307 : LMC anomalous Cepheid Ks light curves (Ripepi+, 2014)
J/A+A/566/L10 : Cepheid radial velocity amplitude modulations (Anderson, 2014)
J/PASP/126/521 : UBVRIJHK photometry of RR Lyrae in M4 (Stetson+, 2014)
J/PASP/126/616 : Variable stars in Leo I dSph (Stetson+, 2014)
J/AcA/64/177 : VI light curves of Galactic Bulge RR Lyrae (Soszynski+, 2014)
J/MNRAS/446/4008 : RT Aur and SZ tau UBV light curves (Evans+, 2015)
J/AJ/150/13 : Cepheid Radial Velocities (CRaV) project (Evans+, 2015)
J/ApJS/219/25 : LCs of RR Lyrae stars in M3 (NGC5272) (Jurcsik+, 2015)
J/AcA/65/233 : OGLE Magellanic Clouds anomalous Cepheids (Soszynski+, 2015)
J/MNRAS/453/2022 : Double-mode radial-non-radial RR Lyrae stars (Netzel+, 2015)
J/AcA/65/297 : OGLE4 LMC and SMC Cepheids (Soszynski+, 2015)
J/MNRAS/455/4231 : Coralie radial velocities for l Car (Anderson+, 2016)
J/MNRAS/463/1707 : l Car radial velocity curves (Anderson, 2016)
J/A+A/603/A70 : Type II & anomalous Cepheids luminosities (Groenewegen+, 2017)
J/A+A/605/A79 : TGAS Cepheids and RR Lyrae stars (Gaia Collaboration+, 2017)
J/AcA/67/297 : OGLE Galactic center Cepheids and RR Lyrae (Soszynski+, 2017)
J/ApJ/850/137 : ISLAndS project. III. Variable stars (Martinez-Vazquez+, 2017)
J/AcA/68/89 : VI light curves of MC type II Cepheids (Soszynski+, 2018)
J/A+A/619/A8 : Cepheid period-luminosity-metallicities (Groenewegen, 2018)
J/ApJ/868/30 : OGLE LMC-T2CEP-211 eclipsing binary LCs & RVs (Pilecki+, 2018)
J/AcA/68/315 : OGLE Galactic Cepheids (Udalski+, 2018)
J/A+A/623/A116 : Gal. Cepheids & RR Lyrae multiplicity. I. (Kervella+, 2019)
J/A+A/623/A146 : Radial Velocity & BIS measurements of Polaris (Anderson, 2019)
J/A+A/625/A14 : Reclassification of Cepheids in the Gaia DR2 (Ripepi+, 2019)
J/ApJS/244/32 : Extended Aperture Photometry of K2 RR Lyrae (Plachy+, 2019)
http://archive.stsci.edu/missions-and-data/tess : TESS data on MAST
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Type Source type (1)
13 A1 --- n_Name Note on Name (2)
15- 32 A18 --- Name Main name of the source
34- 52 A19 --- OName Other name
54- 63 I10 --- TIC [9846652/2027094382] TIC number
65- 76 F12.8 deg RAdeg Gaia barycentric right ascension (ICRS)
at Ep=2015.5
78- 89 F12.8 deg DEdeg Gaia Barycentric declination (ICRS) at Ep=2015.5
91- 96 F6.3 mag RPmag [3.26/16.971] Gaia RP-band magnitude
98-101 A4 --- n_RPmag Note on RPmag (3)
103-111 A9 --- Sector TESS sector(s)
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Note (1): Abbreviations for variable types as follows:
DCEP-F = fundamental-mode classical Cepheid,
DCEP-1O = first-overtone classical Cepheid,
DCEP-F/1O = double-mode classical Cepheid pulsating in fundamental and
first-overtone modes,
DCEP-1O/2O = double-mode classical Cepheid pulsating in first and
second-overtone modes,
ACEP-F = fundamental-mode anomalous Cepheid,
ACEP-1O = first-overtone anomalous Cepheid,
BLH = BL Her type,
pWVir = peculiar W Vir type.
Note (2): Flag as follows:
* = 2 minutes cadence targets
r = Literature variable types were revised for OGLE SMC-CEP-4952 and RV Men.
Note (3): No GRP value is available yet for β Dor; therefore, we gave
the TESS brightness (Tmag).
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Identifier
20- 33 F14.6 d BJD Barycentric Julian Date
35- 43 F9.6 mag Tmag [10.5/17.4] TESS apparent magnitude
45- 52 F8.6 mag e_Tmag [0.00029/0.8] Uncertainty in Tmag
54- 64 F11.6 e/s Flux [19/9961] Tess flux in electrons/s
66- 75 F10.6 e/s e_Flux [0.37/214] Uncertainty in Flux
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 18 F18.10 d BJD Barycentric Julian Date
20- 27 F8.6 mag Tmag [2.8/3.3] TESS apparent magnitude
29- 36 F8.6 mag e_Tmag [0/4.1e-5] Uncertainty in Tmag
38- 45 I8 e/s Flux [7958716/11898840] Tess flux in electrons/s
47- 54 F8.4 e/s e_Flux [297/371] Uncertainty in Flux
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 03-May-2021