Planets Around Low-Mass Stars (PALMS). II. A Low-Mass Companion to the Young M Dwarf GJ 3629 Separated By 0.2"

Abstract

We present the discovery of a 0.2" companion to the young M dwarf GJ 3629 as part of our high contrast adaptive optics imaging search for giant planets around low-mass stars with the Keck-II and Subaru telescopes. Two epochs of imaging confirm the pair is co-moving and reveal signs of orbital motion. The primary exhibits saturated X-ray emission, which together with its UV photometry from GALEX point to an age younger than ~300 Myr. At these ages the companion lies below the hydrogen burning limit with a model-dependent mass of 46 +/- 16 Mjup based on the system's photometric distance of 22 +/- 3 pc. Resolved YJHK photometry of the pair indicates a spectral type of M7 +/- 2 for GJ 3629 B. With a projected separation of 4.4 +/- 0.6 AU and an estimated orbital period of 21 +/- 5 yr, GJ 3629 AB is likely to yield a dynamical mass in the next several years, making it one of only a handful of brown dwarfs to have a measured mass and an age constrained from the stellar primary.

Accepted for publication in ApJ

References in corpus (18)

• Direct Imaging of Multiple Planets Orbiting the Star HR 8799
• Optical Images of an Exosolar Planet 25 Light Years from Earth
• The Evolution of L and T Dwarfs in Color-Magnitude Diagrams
• Constraining the Age-Activity Relation for Cool Stars: The SDSS DR5 Low-Mass Star Spectroscopic Sample
• The Sloan Digital Sky Survey Quasar Catalog IV. Fifth Data Release
• The Gemini Deep Planet Survey -- GDPS
• A New Planet Around an M Dwarf: Revealing a Correlation Between Exoplanets and Stellar Mass
• Planets around evolved intermediate-mass stars. I. Two substellar companions in the open clusters NGC 2423 and NGC 4349
• Direct Imaging and Spectroscopy of a Planetary Mass Candidate Companion to a Young Solar Analog
• Characterizing Young Brown Dwarfs using Low Resolution Near-IR Spectra
• M dwarfs: effective temperatures, radii and metallicities
• JHK Observations of Faint Standard Stars in the Mauna Kea Near-Infrared Photometric System
• Keck Laser Guide Star Adaptive Optics Monitoring of 2MASS J1534-2952AB: First Dynamical Mass Determination of a Binary T Dwarf
• A New Method to Identify Nearby, Young, Low-mass Stars
• Planets Around Low-Mass Stars (PALMS). I. A Substellar Companion to the Young M Dwarf 1RXS J235133.3+312720
• Spitzer/IRAC Limits to Planetary Companions of Fomalhaut and epsilon Eridani
• Dynamical Mass of GJ 802B: a brown dwarf in a triple system
• Dynamical masses for the nearest brown dwarf binary: Epsilon Indi Ba, Bb

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