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Title: Orbits and dynamical masses for the active Hyades multiple system HD 284163
ABSTRACT We report near-infrared long-baseline interferometric observations of the Hyades multiple system HD 284163, made with the Center for High Angular Resolution Astronomy array, as well as almost 43 yr of high-resolution spectroscopic monitoring at the Center for Astrophysics. Both types of observations resolve the 2.39 d inner binary, and also an outer companion in a 43.1 yr orbit. Our observations, combined with others from the literature, allow us to solve for the 3D inner and outer orbits, which are found to be at nearly right angles to each other. We determine the dynamical masses of the three stars (good to better than 1.4 per cent for the inner pair), as well as the orbital parallax. The secondary component (0.5245 ± 0.0047 M⊙) is now the lowest mass star with a dynamical mass measurement in the cluster. A comparison of these measurements with current stellar evolution models for the age and metallicity of the Hyades shows good agreement. All three stars display significant levels of chromospheric activity, consistent with the classification of HD 284163 as an RS CVn object. We present evidence that a more distant fourth star is physically associated, making this a hierarchical quadruple system.  more » « less
Award ID(s):
2034336 2009489 1909165
PAR ID:
10511040
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
527
Issue:
3
ISSN:
0035-8711
Page Range / eLocation ID:
8907 to 8920
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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