The Nearest Isolated Member of the TW Hydrae Association is a Giant Planet Analog
Abstract
In a recent search for unusually red L and T dwarfs, we identified 2MASS J11193254-1137466 as a likely young L7 dwarf and potential member of the TW Hydrae association. We present spectra that confirm the youth of this object. We also measure a radial velocity of 8.5 ± 3.3 km s-1 that, together with the sky position, proper motion, and photometric distance, results in a 92% probability of membership in the TW Hydrae association, with a calibrated field contamination probability of 0.0005% using the BANYAN II tool. Using the age of TW Hydrae and the luminosity of 2MASS J11193254-1137466, we estimate its mass to be 4.3-7.6 {M}{Jup}. It is the lowest-mass and nearest isolated member of TW Hydrae at a kinematic distance of 28.9 ± 3.6 pc, and the second-brightest isolated <10 {M}{Jup} object discovered to date.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2016
- DOI:
- arXiv:
- arXiv:1603.08529
- Bibcode:
- 2016ApJ...821L..15K
- Keywords:
-
- brown dwarfs;
- open clusters and associations: individual: TW Hydrae;
- stars: individual: 2MASS J11193254â1137466;
- techniques: radial velocities;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 6 pages, 3 figures, Accepted for publication in ApJ Letters