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Title: THE EXEMPLAR T8 SUBDWARF COMPANION OF WOLF 1130

We have discovered a wide separation (188.''5) T8 subdwarf companion to the sdM1.5+WD binary Wolf 1130. Companionship of WISE J200520.38+542433.9 is verified through common proper motion over a ∼3 yr baseline. Wolf 1130 is located 15.83 ± 0.96 pc from the Sun, placing the brown dwarf at a projected separation of ∼3000 AU. Near-infrared colors and medium resolution (R ≈ 2000-4000) spectroscopy establish the uniqueness of this system as a high-gravity, low-metallicity benchmark. Although there are a number of low-metallicity T dwarfs in the literature, WISE J200520.38+542433.9 has the most extreme inferred metallicity to date with [Fe/H] = –0.64 ± 0.17 based on Wolf 1130. Model comparisons to this exemplar late-type subdwarf support it having an old age, a low metallicity, and a small radius. However, the spectroscopic peculiarities of WISE J200520.38+542433.9 underscore the importance of developing the low-metallicity parameter space of the most current atmospheric models.
Authors:
; ; ; ;  [1] ; ; ;  [2] ;  [3] ;  [4] ;  [5]
  1. Department of Physics and Astronomy, UCLA, 430 Portola Plaza, Box 951547, Los Angeles, CA 90095-1547 (United States)
  2. Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States)
  3. Department of Physics and Astronomy, MS 111, University of Toledo, 2801 W. Bancroft St., Toledo, OH 43606-3328 (United States)
  4. Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States)
  5. NASA Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
Publication Date:
OSTI Identifier:
22270676
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 777; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; BENCHMARKS; COLOR; COMPARATIVE EVALUATIONS; DWARF STARS; GRAVITATION; HYDROGEN; INFRARED SPECTRA; IRON; MASS; NEAR INFRARED RADIATION; PROPER MOTION; RESOLUTION; SPACE; SUN