Astrophysics, abstract
astro-ph/0609556

From: Adam J. Burgasser [view email]

Date: Wed, 20 Sep 2006 00:36:50 GMT (19kb)

The Spectrum of HD 3651B: An Extrasolar Nemesis?

Authors: Adam J. Burgasser (MIT)

Comments: 12 pages, 2 figures, submitted to ApJ Letters on Sept 6th before I was aware of the Luhman et al. ApJ paper astro-ph/0609464

I present detailed analysis of the near-infrared spectrum of HD 3651B, a faint, co-moving wide companion to the nearby planet-hosting star HD 3651. The presence of strong H_2O and CH_4 absorption bands confirm this source as a late T-type brown dwarf with spectral type T8. Application of the technique of Burgasser, Burrows & Kirkpatrick yields T_eff = 840+/-80 K, log(g) = 4.9+/-0.2, M = 30+/-10 M_Jup and an age in the range 0.7-3.4 Gyr, making HD 3651B a slightly warmer analog to the field T8 2MASS 0415-0935. The derived age for this companion is somewhat better constrained than estimates for its primary, which ranges from ~2 Gyr to >12 Gyr.

As a widely orbiting massive object to a known planetary system that could potentially harbor terrestrial planets in its habitable zone, HD 3651B may play the role of Nemesis in this system.

http://arxiv.org/abs/astro-ph/0609556