Bibcode
Iglesias-Marzoa, Ramón; Arévalo, María J.; López-Morales, Mercedes; Torres, Guillermo; Lázaro, Carlos; Coughlin, Jeffrey L.
Bibliographical reference
Astronomy and Astrophysics, Volume 627, id.A153, 14 pp.
Advertised on:
7
2019
Journal
Citations
3
Refereed citations
3
Description
Context. Low-mass stars in eclipsing binary systems show radii larger
and effective temperatures lower than theoretical stellar models predict
for isolated stars with the same masses. Eclipsing binaries with
low-mass components are hard to find due to their low luminosity. As a
consequence, the analysis of the known low-mass eclipsing systems is key
to understand this behavior. Aims: We aim to investigate the
mass-radius relation for low-mass stars and the cause of the deviation
of the observed radii in low-mass detached eclipsing binary stars
(LMDEB) from theoretical stellar models. Methods: We developed a
physical model of the LMDEB system NSVS 10653195 to accurately measure
the masses and radii of the components. We obtained several
high-resolution spectra in order to fit a spectroscopic orbit.
Standardized absolute photometry was obtained to measure reliable color
indices and to measure the mean Teff of the system in
out-of-eclipse phases. We observed and analyzed optical VRI and infrared
JK band differential light-curves which were fitted using PHOEBE. A
Markov chain Monte-Carlo (MCMC) simulation near the solution found
provides robust uncertainties for the fitted parameters. Results:
NSVS 10653195 is a detached eclipsing binary composed of two similar
stars with masses of M1 = 0.6402 ± 0.0052
M⊙ and M2 = 0.6511 ± 0.0052
M⊙ and radii of R1 =
0.687+0.017-0.024 R⊙ and
R2 = 0.672+0.018-0.022
R⊙. Spectral types were estimated to be K6V and K7V.
These stars rotate in a circular orbit with an orbital inclination of i
= 86.22 ± 0.61 degrees and a period of P = 0.5607222(2) d. The
distance to the system is estimated to be d =
135.2+7.6-7.9 pc, in excellent agreement with the
value from Gaia. If solar metallicity were assumed, the age of the
system would be older than log (age) ˜ 8 based on the
Mbol-log Teff diagram. Conclusions: NSVS
10653195 is composed of two oversized and active K stars. While their
radii is above model predictions their Teff are in better
agreement with models.
Full Tables 1-3 and 7 are only available at the CDS via anonymous ftp to
http://cdsarc.u-strasbg.fr
(ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A153
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