High resolution visible spectroscopy of the jet-driving star Th 28?

Received; accepted Context. We present a study of the extreme T Tauri star Th 28, a young stellar object in the Lupus 3 cloud whose spectrum displays all the variety of signposts associated with early stellar activity. Th 28 is the driving source of a fast jet, and it is thus a very promising target to study the disk-jet connection. Aims. We try to identify and investigate the different structural components that contribute to the different emission lines in the spectrum of the Th 28 central source. Methods. We have obtained high resolution visible spectroscopy with the UVES spectrograph at the VLT, using the resolved profiles of both permitted and forbidden lines as tracers of gas with different kinematic and physical properties, complemented with other observations from the literature. Results. We identify four distinct structural components that contribute to the visible emission-line spectrum of Th 28. The first one, dominating most of the permitted and forbidden lines, is probably associated with the origin of the outflow that produced in the past the Herbig-Haro objects seen to the west of Th 28. The second one is an uncollimated stellar wind characterized by a high excitation and temperature, as shown by the broad profile of the intense [OIII] lines. The third component, traced only by permitted lines, appears as a redshifted tail extending up to radial velocities of +450 km s−1, which we attribute to magnetospheric accretion. From this latte