Serendipitous discovery of seven new southern L-dwarfs

¹ Centro de Astronomia e Astrofísica da Universidade de Lisboa, Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisboa, Portugal
² Groupe d'Astrophysique, UMR-5024 CNRS, Case 072, place Bataillon, 34095 Montpellier Cedex 05, France
³ IAM, Observatoire de Marseille, 2 place Le Verrier, 13248 Marseille Cedex 04, France
⁴ 378433 Byukaran Astrophysical Observatory & Isaac Newton Institute of Chile, Armenian Branch, Ashtarak d-ct, Armenia

Corresponding author: T. R. Kendall, tkendall@oal.ul.pt

Received: 16 December 2002
Accepted: 12 February 2003

Abstract

We report the discovery of seven hitherto unknown L-dwarfs found as a result of a spectroscopic search for distant AGB stars. Their far-red and near-infrared colours are very similar to known dwarfs of the same spectral type. One new object is among the ~30 brightest L-dwarfs, with , and is nearby, ~20 pc. Using low resolution spectroscopy from the Danish 1.54 m ESO telescope, spectral types in the range L0.5–L5 are derived for these seven L-dwarfs by direct comparison to L-type standards taken from Kirkpatrick et al. (1999). Distances are determined from existing calibrations, and together with measured proper motions, yield kinematics for the seven new dwarfs consistent with that expected for the solar neighbourhood disk population.