AN M DWARF COMPANION TO AN F-TYPE STAR IN A YOUNG MAIN-SEQUENCE BINARY
Journal article, 2016
Only a few well characterized very low-mass M dwarfs are known today. Our understanding of M dwarfs is vital as these are the most common stars in our solar neighborhood. We aim to characterize the properties of a rare F+dM stellar system for a better understanding of the low-mass end of the Hertzsprung-Russel diagram. We used photometric light curves and radial velocity follow-up measurements to study the binary. Spectroscopic analysis was used in combination with isochrone fitting to characterize the primary star. The primary star is an early F-type main-sequence star with a mass of (1.493 +/- 0.073) M-circle dot and a radius of (1.474 +/- 0.040) R-circle dot. The companion is an M dwarf with a mass of (0.188 +/- 0.014) M-circle dot and a radius of (0.234 +/- 0.009) R-circle dot. The orbital period is (1.35121 +/- 0.00001) days. The secondary star is among the lowest-mass M dwarfs known to date. The binary has not reached a 1: 1 spin-orbit synchronization. This indicates a young main-sequence binary with an age below similar to 250 Myr. The mass-radius relation of both components are in agreement with this finding.
stars: evolution
binaries: eclipsing
stars: low-mass
binaries: close
Author
Philipp Eigmüller
German Aerospace Center (DLR)
Thüringer Landessternwarte Tautenburg
J. Eisloffel
Thüringer Landessternwarte Tautenburg
S. Csizmadia
German Aerospace Center (DLR)
H. Lehmann
Thüringer Landessternwarte Tautenburg
A. Erikson
German Aerospace Center (DLR)
Malcolm Fridlund
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
M. Hartmann
Thüringer Landessternwarte Tautenburg
A. Hatzes
Thüringer Landessternwarte Tautenburg
T. Pasternacki
German Aerospace Center (DLR)
H. Rauer
German Aerospace Center (DLR)
Technische Universität Berlin
A. Tkachenko
KU Leuven
H. Voss
University of Barcelona
Astronomical Journal
0004-6256 (ISSN) 1538-3881 (eISSN)
Vol. 151 3 84Subject Categories
Astronomy, Astrophysics and Cosmology
DOI
10.3847/0004-6256/151/3/84