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arXiv · 1407.5344

SIMP J2154-1055: A New Low-Gravity L4$\beta$ Brown Dwarf Candidate Member of the Argus Association

Jonathan Gagné·David Lafrenière·René Doyon·Étienne Artigau·Lison Malo·Jasmin Robert·Daniel Nadeau
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Abstract

We present SIMP J21543454-1055308, a new L4$\beta$ brown dwarf identified in the Sondage Infrarouge de Mouvement Propre (SIMP) survey that displays signs of low gravity in its near-infrared spectrum. Using the Bayesian Analysis for Nearby Young AssociatioNs II (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 $\pm$ 0.5 $M_{\mathrm{Jup}}$.

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Jonathan Gagné, David Lafrenière, René Doyon, Étienne Artigau, Lison Malo, Jasmin Robert, Daniel Nadeau. 2014-07-20. SIMP J2154-1055: A New Low-Gravity L4$\beta$ Brown Dwarf Candidate Member of the Argus Association. https://doi.org/10.1088/2041-8205/792/1/l17

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