Searching for Brown Dwarf Outflows

As outflow activity in low mass protostars is strongly connected to ac- cretion it is reasonable to expect accreting brown dwarfs to also be driving out- flows. In the last three years we have searched for brown dwarf outflows using high quality optical spectra obtained with UVES on the VLT and the technique of spectro-astrometry. To date five brown dwarf outflows have been discovered. Here the method is discussed and the results to date outlined.

💡 Research Summary

The paper investigates whether accreting brown dwarfs (BDs) drive outflows in a manner analogous to low‑mass protostars, whose outflow activity is tightly linked to accretion processes. Over the past three years the authors have employed the Ultraviolet and Visual Echelle Spectrograph (UVES) on the Very Large Telescope (VLT) to obtain high‑resolution optical spectra of a sample of young brown dwarfs known to possess circum‑stellar disks. The key methodological tool is spectro‑astrometry, a technique that measures the centroid position of an emission line as a function of wavelength with sub‑milli‑arcsecond precision, thereby revealing spatial offsets that are far below the conventional imaging resolution limit.

Using this approach, the team has identified five brown dwarfs that exhibit clear signatures of bipolar outflows. In each case, classic jet tracers such as Hα,