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arXiv · 1205.0818

Discovery of Two Very Wide Binaries with Ultracool Companions and a New Brown Dwarf at the L/T Transition

Koraljka Muzic·Jacqueline Radigan·Ray Jayawardhana·Valentin D. Ivanov·Jacqueline K. Faherty·Radostin G. Kurtev·Alejandro Nunez·Henri M. J. Boffin·Olivier Hainaut·Kelle Cruz·David Jones·Stanimir Metchev·Amy Tyndall·Jura Borissova
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Abstract

We present the discovery and spectroscopic follow-up of a nearby late-type L dwarf (2M0614+3950), and two extremely wide very-low-mass binary systems (2M0525-7425AB and 2M1348-1344AB), resulting from our search for common proper motion pairs containing ultracool components in the Two Micron All Sky Survey (2MASS) and the Wide-field Infrared Survey Explorer (WISE) catalogs. The near-infrared spectrum of 2M0614+3950 indicates a spectral type L$9 \pm 1$ object residing at a distance of $26.0 \pm 1.8$ pc. The optical spectrum of 2M0525-7425A reveals an M$3.0 \pm 0.5$ dwarf primary, accompanied by a secondary previously classified as L2. The system has an angular separation of $\sim 44"$, equivalent to $\sim 2000 $AU at distance of $46.0 \pm 3.0$ pc. Using optical and infrared spectra, respectively, we classify the components of 2M1348-1344AB as M$4.5 \pm 0.5$ and T$5.5 \pm 1$. The angular separation of $\sim 68"$ is equivalent to $\sim 1400 $AU at a distance of $20.7 \pm 1.4$ pc. 2M1348-1344AB is one of only six very wide (separation $>$ 1000 AU) systems containing late T dwarfs known to date.

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Koraljka Muzic, Jacqueline Radigan, Ray Jayawardhana, Valentin D. Ivanov, Jacqueline K. Faherty, Radostin G. Kurtev, Alejandro Nunez, Henri M. J. Boffin, Olivier Hainaut, Kelle Cruz, David Jones, Stanimir Metchev, Amy Tyndall, Jura Borissova. 2012-05-03. Discovery of Two Very Wide Binaries with Ultracool Companions and a New Brown Dwarf at the L/T Transition. https://doi.org/10.1088/0004-6256/144/6/180

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