SIMP J2154–1055: A New Low-gravity L4β Brown Dwarf Candidate Member of the Argus Association

  title={SIMP J2154–1055: A New Low-gravity L4$\beta$ Brown Dwarf Candidate Member of the Argus Association},
  author={Jonathan Gagn'e and David Lafreni{\`e}re and Ren{\'e} Doyon and 'Etienne Artigau and Lison Malo and Jasmin Robert and Daniel Nadeau},
  journal={The Astrophysical Journal},
We present SIMP J21543454–1055308, a new L4β brown dwarf identified in the SIMP survey that displays signs of low gravity in its near-infrared spectrum. Using BANYAN II, we show that it is a candidate member of the Argus association, albeit with a 21% probability that it is a contaminant from the field. Measurements of radial velocity and parallax will be needed to verify its membership. If it is a member of Argus (age 30-50 Myr), then this object would have a planetary mass of 10 ± 0.5 M Jup. 

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