J/A+A/623/A23 Differential photometry of MML 53 (Gomez Maqueo Chew+, 2019)
Fundamental properties of the pre-main sequence eclipsing stars of MML 53
and the mass of the tertiary.
Gomez Maqueo Chew Y., Hebb L., Stempels H.C., Paat A., Stassun K.G.,
Faedi F., Street R.A., Rohn G., Hellier C., Anderson D.R.
<Astron. Astrophys. 623, A23 (2019)>
=2019A&A...623A..23G 2019A&A...623A..23G (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Stars, fundamental ;
Stars, pre-main sequence ; Photometry
Keywords: binaries: eclipsing - binaries: spectroscopic -
stars: fundamental parameters - stars: pre-main sequence -
stars: low-mass - stars: individual MML 53
Abstract:
We present the most comprehensive analysis to date of the Upper
Centaurus Lupus eclipsing binaryMML53 (with PEB=2.097892d), and for
the first time, confirm the bound-nature of the third star (in a
P3∼9yr orbit) by constraining its mass dynamically. Our analysis is
based on new and archival spectra and time-series photometry, spanning
80% of one orbit of the outer component. From the spectroscopic
analysis, we determined the temperature of the primary star to be
4880±100K. The study of the close binary incorporated treatment of
spots and dilution by the tertiary in the light curves, allowing for
the robust measurement of the masses of the eclipsing components
within 1% (M1=1.0400±0.0067M☉ and M2=0.8907±0.0058M☉),
their radii within 4.5% (R1=1.283±0.043R☉ and
R2=1.107±0.049R☉), and the temperature of the secondary star
(Teff,2=4379±100K). From the analysis of the eclipse timings, and
the change in systemic velocity of the eclipsing binary and the radial
velocities of the third star, we measured the mass of the outer
companion to be 0.7M☉ (with a 20% uncertainty). The age we
derived from the evolution of the temperature ratio between the
eclipsing components is fully consistent with previous, independent
estimates of the age of Upper Centaurus Lupus (16±2Myr). At this
age, the tightening of the MML53 eclipsing binary has already
occurred, thus supporting close-binary formation mechanisms that act
early in the stars' evolution. The eclipsing components of MML53
roughly follow the same theoretical isochrone, but appear to be
inflated in radius (by 20% for the primary and 10% for the secondary)
with respect to recent evolutionary models. However, our radius
measurement of the 1.04M☉ primary star of MML53 is in full
agreement with the independent measurement of the secondary of NP Per
which has the same mass and a similar age. The eclipsing stars of
MML53 are found to be larger but not cooler than predicted by
non-magnetic models, it is not clear what is the mechanism that is
causing the radius inflation given that activity, spots and/or
magnetic fields slowing their contraction, require the inflated stars
to be cooler to remain in thermal equilibrium.
Description:
These tables include the light curves of MML 53 showing the eclipsing
nature of the close stellar components and including dilution by the
tertiary star. We present all the available WASP data from 2006 to
2013 (Table 1), and the follow-up photometry from the 2m Faulkes
Telescope South (Table 2) and the photometry from the 1m SMARTS
telescope at Cerro Tololo Interamerican Observatory (Table 3).
Objects:
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RA (2000) DE Designation(s)
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14 58 37.69 -35 40 30.4 MML 53 = CD-35 9931
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
swasp.dat 26 135061 WASP photometry from 2006 to 2013
fts.dat 26 423 FTS photometry in V-band
ctio.dat 26 1754 CTIO 1m photometry in UBVRcIc
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Byte-by-byte Description of file: swasp.dat fts.dat
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Bytes Format Units Label Explanations
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1- 10 F10.5 d HJD Heliocentric Julian day (HJD-2450000)
12- 18 F7.4 mag Dmag Differential photometry in magnitude
20- 26 F7.4 mag e_Dmag Photometric error
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Byte-by-byte Description of file: ctio.dat
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Bytes Format Units Label Explanations
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1- 10 F10.5 d BJD Barycentric Julian day (TDB) (BJD-2450000)
12- 17 F6.3 mag Dmag Differential photometry in magnitude
19- 23 F5.3 mag e_Dmag Photometric error
25- 26 A2 --- Filter [UBVRIc ] Photometric filter (U,B,V,Rc or Ic)
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Acknowledgements:
Yilen Gomez Maqueo Chew, ygmc(at)astro.unam.mx
(End) Patricia Vannier [CDS] 07-Feb-2019