Discovery of three nearby L dwarfs in the Southern Sky

Abstract

We report the discovery of three L dwarfs in the solar vicinity within 30 parsecs. These objects were originally found as proper motion objects from a combination of R and I photographic plates measured as part of the SuperCOSMOS Sky Surveys. We subsequently identified these objects as bona fide brown dwarf candidates on the basis of their R-I colour, as first criterion, and subsequently their J-K colours when the infrared data were available from the 2MASS database. Spectroscopic observations in the optical with the ESO 3.6m/EFOSC2 and in the near-infrared with the NTT/SOFI led to the classification of their spectral types as early L dwarfs.