J/A+A/645/A25 HD27130 photometric light curves (Brogaard+, 2021)
Properties of the Hyades, the eclipsing binary HD27130, and the oscillating
red giant epsilon Tau.
Brogaard K., Pakstiene E., Grundahl F., Mikolaitis S., Tautvaisiene G.,
Slumstrup D., Talens G.J.J., VandenBerg D.A., Miglio A., Arentoft T.,
Kjeldsen H., Janulis R., Drazdauskas A., Marchini A., Minkeviciute R.,
Stonkute E., Bagdonas V., Fredslund Andersen M., Jessen-Hansen J.,
Palle P.L., Dorval P., Snellen I.A.G., Otten G.P.P.L., White T.R.
<Astron. Astrophys. 645, A25 (2021)>
=2021A&A...645A..25B 2021A&A...645A..25B (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Photometry, CCD ; Optical
Keywords: binaries: eclipsing -
open clusters and associations: individual: Hyades -
stars: oscillations - stars: abundances -
stars: individual: HD 27130 - stars: individual: epsilon Tau
Abstract:
The derivation of accurate and precise masses and radii is possible
for eclipsing binary stars, allowing for insights into their
evolution. When residing in star clusters, they provide measurements
of even greater precision, along with additional information on their
properties. Asteroseismic investigations of solar-like oscillations
offers similar possibilities for single stars.
We wish to improve the previously established properties of the Hyades
eclipsing binary HD 27130 and re-assess the asteroseismic properties
of the giant star ε Tau. The physical properties of these
members of the Hyades can be used to constrain the helium content and
age of the cluster.
New multi-colour light curves were combined with multi-epoch radial
velocities to yield masses and radii of HD 27130. Measurements of Teff
were derived from spectroscopy and photometry, and verified using the
Gaia parallax. We estimated the cluster age from re-evaluated
asteroseismic properties of ε Tau while using HD 27130 to
constrain the helium content.
The masses, radii, and Teff of HD 27130 were found to be
M=1.0245±0.0024M☉, R=0.9226±0.015R☉, Teff=5650±50K
for the primary, and M=0.7426±0.0016M☉,
R=0.7388±0.026R☉, Teff=4300±100K for the secondary
component. Our re-evaluation of ε Tau suggests that the
previous literature estimates are trustworthy and that the HIPPARCOS
parallax is more reliable than the Gaia DR2 parallax.
The helium content of HD 27130 and, thus, of the Hyades is found to be
Y=0.27 but with a significant model dependency. Correlations with the
adopted metallicity result in a robust helium enrichment law, with
{DELTA}Y/{DELTA}Z close to 1.2 We estimate the age of the Hyades to be
0.9±0.1(stat)±0.1(sys)Gyr, which is in slight tension with recent
age estimates based on the cluster white dwarfs. The precision of the
age estimate can be much improved via asteroseismic investigations of
the other Hyades giants and by future improvements to the Gaia
parallax for bright stars.
Description:
We obtained photometric light curves (LCs) for HD 27130 in Johnson B,
V, and Cousins I bandpasses at the Moletai Astronomical Observatory of
Vilnius University (MAO, Lithuania) and the Astronomical Observatory
of the University of Siena (AO SU, Italy). We also obtained the
photometric light curve of HD 27130 from the MASCARA survey. These
observed light curves are found in Tables 8-13.
For Modelling purposes, we combined and manipulated the light curves
to remove out-of-eclipse variations, and to only include observations
in or very close to eclipse. These corrected light curves are
normalised to 0 mag and available in Tables 14-16.
Objects:
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RA (2000) DE Designation(s)
----------------------------------------------------
04 17 38.95 +16 56 52.2 HD 27130 = BD+16 577
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table8.dat 73 28170 MASCARA LC of HD 27130
table9.dat 38 3592 LC of HD 27130 in Johnson B-band from MAO
table10.dat 38 3929 LC of HD 27130 in Johnson V-band from MAO
table11.dat 38 3679 LC of HD 27130 in Cousins I-band from MAO
table12.dat 40 331 LC of HD 27130 in Johnson V-band from AO SU
table13.dat 40 327 LC of HD 27130 in Cousins I-band from AO SU
table14.dat 34 865 Corrected LC of HD 27130 in Johnson V-band
table15.dat 34 750 Corrected LC of HD 27130 in Cousins I-band
table16.dat 40 1814 Corrected MASCARA LC of HD 27130
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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- 13 F13.5 d BJD Barycentric Julian date (TDB), BJD-2400000
15- 23 F9.6 --- LST Local sidereal time of the observation
25- 33 F9.6 mag mag Magnitude after primary calibration
35- 43 F9.6 mag e_mag Uncertainty on mag
45- 53 F9.6 mag Legendre Model of trends from secondary calibration,
this should be subtracted from MAG to obtain
the lightcurve shown in the paper
55- 63 F9.6 --- Phase Phase of the binary
65- 73 F9.6 mag Model Running mean in PHASE obtained as part of
disentangling the secondary calibration and
binary signal (as described in the paper)
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Byte-by-byte Description of file: table9.dat table1[0123].dat
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Bytes Format Units Label Explanations
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1- 15 F15.7 d BJD Barycentric Julian date (TDB), BJD-2400000
17- 25 F9.6 mag mag Photomeric magnitude in Band
27- 32 F6.4 mag e_mag Uncertainty on photometric magnitude
34 A1 --- Band [BVI ] Band for magnitude
36- 40 A5 --- Inst [MAO AO SU] Instrument (MAO or AO SU)
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Byte-by-byte Description of file: table14.dat table15.dat table16.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 F15.7 d BJD Barycentric Julian date (TDB), BJD-2400000
17- 25 F9.6 mag mag Photomeric magnitude in Band, corrected,
normalised
27- 32 F6.4 mag e_mag Uncertainty on photometric magnitude
34- 40 A7 --- Band [VI MASCARA ] Band for magnitude
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Acknowledgements:
Karsten Brogaard, kfb(at)phys.au.dk
(End) Patricia Vannier [CDS] 13-Nov-2020