WISEA J114724.10-204021.3: A Free-floating Planetary Mass Member of the TW Hya Association

May 2016 • 2016ApJ...822L...1S

Authors • Schneider, Adam C. • Windsor, James • Cushing, Michael C. • Kirkpatrick, J. Davy • Wright, Edward L.

Abstract • We present WISEA J114724.10-204021.3, a young, low-mass, high-probability member of the TW Hya association (TWA). WISEA J114724.10-204021.3 was discovered based on its red AllWISE color (W1 - W2 = 0.63 mag) and extremely red 2MASS J - K _S color (>2.64 mag), the latter of which is confirmed with near-infrared photometry from the Visible and Infrared Survey Telescope for Astronomy Hemisphere Survey (J - K _S = 2.57 ± 0.03). Follow-up near-infrared spectroscopy shows a spectral type of L7 ± 1 as well as several spectroscopic indicators of youth. These include a peaked H-band shape and a steeper K-band slope, traits typically attributed to low surface gravity. The sky position, proper motion, and distance estimates of WISEA J114724.10-204021.3 are all consistent with membership in the ∼10 Myr old TWA. Using the age of the TWA and evolutionary models, we estimate the mass of WISEA J114724.10-204021.3 to be 5-13 M _Jup, making it one of the youngest and lowest-mass free-floating objects yet discovered in the Solar neighborhood.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2016ApJ...822L...1S
• PDF https://iopscience.iop.org/article/10.3847/2041-8205/822/1/L1/pdf
• PDF https://stacks.iop.org/2041-8205/822/L1/pdf
• PREPRINT http://arxiv.org/abs/1603.07985
• DATA http://archive.eso.org/bin/ads2eso?2016ApJ...822L...1S
• DATA https://irsa.ipac.caltech.edu/bibdata/2016/S/2016ApJ...822L...1S.html
• ELECTR https://doi.org/10.3847%2F2041-8205%2F822%2F1%2FL1