surveys;
stars : distances;
stars : kinematics;
stars : late-type;
stars;
low-mass;
brown dwarfs;
solar neighbourhood;
D O I:
10.1051/0004-6361:20020698
中图分类号:
P1 [天文学];
学科分类号:
0704 ;
摘要:
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 ESO3.6 m/EFOSC2 and in the near-infrared with the NTT/SOFI led to the classification of their spectral types as early L dwarfs.