SIMBAD references

2007ApJ...655..522L - Astrophys. J., 655, 522-527 (2007/January-3)

On the nature of the unique Hα-emitting T dwarf 2MASS J12373919+6526148.

LIEBERT J. and BURGASSER A.J.

Abstract (from CDS):

We explore and discount the hypothesis that the strong, continual Hα-emitting T dwarf 2MASS J12373919+6526148 can be explained as a young, low-gravity, very low mass brown dwarf. The source is already known to have a marginally fainter absolute magnitude than similar T dwarfs with trigonometric parallax measurements and has a tangential velocity consistent with old disk kinematics. Applying the technique of Burgasser et al. on new near-infrared spectroscopy for this source, estimates of its Teff, logg, and metallicity ([M/H]) are obtained. 2M 1237+6526 has a Teff~800-850 K. If [M/H] is solar, logg is as high as ∼5.5 (cgs) and this source is older than 10 Gyr. We find a more plausible scenario to be a modestly subsolar metallicity ([M/H]=-0.2) and moderate logg∼5.0, implying an age older than 2 Gyr and a mass greater than 0.035 M. The alternative explanation of the unique emission of this source, involving an interacting, close, double degenerate system, should be investigated further. Indeed, there is some evidence of a Teff<500 K companion to 2M 1237+6526 on the basis of a possible Spitzer IRAC [3.6]-[4.5] color excess. This excess may, however, be caused by a subsolar metallicity.

Abstract Copyright:

Journal keyword(s): stars: individual (2MASS J12373919+6526148) - Stars: Low-Mass, Brown Dwarfs - Techniques: Spectroscopic

Simbad objects: 11

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2007ApJ...655..522L and select 'bookmark this link' or equivalent in the popup menu