Intense accretion and mass loss of a very low mass young stellar object

We present visible and near-infrared photometry and spectroscopy of LS-RCrA 1, a faint, very late-type object (M 6.5-M 7) seen in the direction of the R Coronae Australis star forming complex. While its emission spectrum show s prominent features of accretion and mass loss typical of young stellar ob jects, its underlying continuum and photometric properties are puzzling whe n trying to derive a mass and age based on pre-main sequence evolutionary t racks: the object appears to be far too faint for a young member of the R C oronae Australis complex of its spectral type. We speculate that this may b e due to either its evolution along pre-main sequence tracks being substant ially altered by the intense accretion, or to a combination of partial bloc king and scattering of the light of the object by a nearly edge-on circumst ellar disk. The rich emission line spectrum superimposed on the stellar con tinuum is well explained by an intense accretion process: the H-alpha, CaII infrared triplet, and HeI 6678 lines show equivalent widths typical of ver y active classical T Tauri stars. The near-infrared observations show anoma lously weak spectral features and no significant excess emission in the K b and, which we tentatively interpret as indicating line filling due to emiss ion in a magnetic accretion funnel ow. At the same time, numerous, strong f orbidden optical lines ([OI], [NII] and [SII]) and H-2 emission at 2.12 mum suggest that the object is simultaneously undergoing mass loss, providing another example that shows that mass loss and accretion are closely related processes. Such an intense accretion and mass loss activity is observed fo r the first time in a young stellar object in the transition region between low mass stars and brown dwarfs, and provides a valuable observational tes t on the effects of accretion on the evolution of objects with such low mas ses.