Direct Imaging and Spectroscopy of a Candidate Companion Below/Near the Deuterium-Burning Limit In The Young Binary Star System, ROXs 42B

Abstract

We present near-infrared high-contrast imaging photometry and integral field spectroscopy of ROXs 42B, a binary M0 member of the 1--3 Myr-old $\rho$ Ophiuchus star-forming region, from data collected over 7 years. Each data set reveals a faint companion -- ROXs 42Bb -- located $\sim$ 1.16" ($r_{proj}$ $\approx$ 150 $AU$) from the primaries at a position angle consistent with a point source identified earlier by Ratzka et al. (2005). ROXs 42Bb's astrometry is inconsistent with a background star but consistent with a bound companion, possibly one with detected orbital motion. The most recent data set reveals a second candidate companion at $\sim$ 0.5" of roughly equal brightness, though preliminary analysis indicates it is a background object. ROXs 42Bb's $H$ and $K_s$ band photometry is similar to dusty/cloudy young, low-mass late M/early L dwarfs. $K$-band VLT/SINFONI spectroscopy shows ROXs 42Bb to be a cool substellar object (M8--L0; $T_{eff}$ $\approx$ 1800--2600 $K$), not a background dwarf star, with a spectral shape indicative of young, low surface gravity planet-mass companions. We estimate ROXs 42Bb's mass to be 6--15 $M_J$, either below the deuterium burning limit and thus planet mass or straddling the deuterium-burning limit nominally separating planet-mass companions from other substellar objects. Given ROXs 42b's projected separation and mass with respect to the primaries, it may represent the lowest mass objects formed like binary stars or a class of planet-mass objects formed by protostellar disk fragmentation/disk instability, the latter slightly blurring the distinction between non-deuterium burning planets like HR 8799 bcde and low-mass, deuterium-burning brown dwarfs.

7 pages, 4 figures, some minor text changes, more references added, ApJ Letters in press

References in corpus (8)

• Direct Imaging of Multiple Planets Orbiting the Star HR 8799
• Optical Images of an Exosolar Planet 25 Light Years from Earth
• Detection of Carbon Monoxide and Water Absorption Lines in an Exoplanet Atmosphere
• A Submillimeter View of Circumstellar Dust Disks in $\rho$ Ophiuchus
• 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
• Discovery of a wide companion near the deuterium burning mass limit in the Upper Scorpius association
• Rapid Formation of Icy Super-Earths and the Cores of Gas Giant Planets

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