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Title: Orbits and Dynamical Masses for Six Binary Systems in the Hyades Cluster
Abstract We report long-baseline interferometric observations with the CHARA Array that resolve six previously known double-lined spectroscopic binary systems in the Hyades cluster, with orbital periods ranging from 3 to 358 days: HD 27483, HD 283882, HD 26874, HD 27149, HD 30676, and HD 28545. We combine those observations with new and existing radial-velocity measurements, to infer the dynamical masses for the components as well as the orbital parallaxes. For most stars, the masses are determined to be better than 1%. Our work significantly increases the number of systems with mass determinations in the cluster. We find that, while current models of stellar evolution for the age and metallicity of the Hyades are able to reproduce the overall shape of the empirical mass–luminosity relation, they overestimate theV-band fluxes by about 0.1 mag between 0.5 and 1.4M⊙. The disagreement is smaller inH, and near zero inK, and depends somewhat on the model. We also make use of the TESS light curves to estimate rotation periods for our targets, and detect numerous flares in one of them (HD 283882), estimating an average flaring rate of 0.44 events per day.  more » « less
Award ID(s):
2034336 1909165
PAR ID:
10536137
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
The Astrophysical Journal
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
971
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
31
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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