2008/08/25 by Chad F. Bender, C. F. Bender, M. Simon · 50 citations
Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Binary number #Binary star #Brown dwarf #Cluster (spacecraft) #Infrared #Low Mass #Luminosity #Mass ratio #Orbital elements #Photometry (optics) #Physics #Star cluster #Stars #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/592728
published in The Astrophysical Journal 689(1), 416-429 (IOP Publishing) · 36 pages, 8 figures, accepted for publication in The Astrophysical Journal
arxiv created 2008/08/25 · openalex publication_date 2008/11/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We have observed a large sample of spectroscopic binary stars in the Hyades cluster, using high-resolution infrared spectroscopy to detect low-mass companions. We combine our double-lined infrared measurements with well-constrained orbital parameters from visible light single-lined observations to derive dynamical mass ratios. Using these results, along with photometry and theoretical mass-luminosity relationships, we estimate the masses of the individual components in our binaries. In this paper we present double-lined solutions for 25 binaries in our sample, with mass ratios from ~0.1 to 0.8. This corresponds to secondary masses as small as ~0.15 M ☉ . We include here our preliminary detection of the companion to vB 142, with a very small mass ratio of q = 0.06 ± 0.04; this indicates that the companion may be a brown dwarf. This paper is an initial step in a program to produce distributions of mass ratio and secondary mass for Hyades cluster binaries with a wide range of periods, in order to better understand binary star formation. As such, our emphasis is on measuring these distributions, not on measuring precise orbital parameters for individual binaries.