159 research outputs found
The Nearest Isolated Member of the TW Hydrae Association is a Giant Planet Analog
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 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 MJup. 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 MJup object discovered to date.Comment: 6 pages, 3 figures, Accepted for publication in ApJ Letter
Discovery of a Possible Early-T Thick-Disk Subdwarf from the AllWISE2 Motion Survey
We have discovered a potential T0 1 subdwarf from a search for sources
in the AllWISE2 Motion Survey that do not have counterparts in surveys at
shorter wavelengths. With a tangential velocity of 170 kms, this object -
WISE J071121.36-573634.2 - has kinematics that are consistent with the
thick-disk population of the Milky Way. Spectral fits suggest a low-metallicity
for this object but also allow for the possibility of unresolved multiplicity.
If WISE J0711-5736 is indeed an sdT0 dwarf, it would be only the second early-T
subdwarf discovered to date.Comment: 11 pages, 6 figures, accepted to A
- …