Herbig-Haro Objects - Tracers of the Formation of Low-mass Stars and Sub-stellar Objects

TL;DR

Herbig-Haro objects serve as indicators of star and sub-stellar object formation, with recent evidence suggesting brown dwarfs can also produce outflows, indicating similar formation processes to stars.

Contribution

The paper presents a survey linking Herbig-Haro objects to young low-mass and sub-stellar objects, providing evidence that brown dwarfs may form via star-like accretion processes.

Findings

Detection of HHOs associated with low-mass stars and brown dwarfs.

Infrared observations support disk presence around brown dwarfs.

Outflow activity observed near the sub-stellar mass limit.

Abstract

Herbig-Haro objects (HHOs) are caused by outflows from young objects. Since the outflow relies on mass accretion from a circumstellar disk, it indicates ongoing growth. Recent results of infrared observations yielded evidence for disks around brown dwarfs. This suggests that at least a certain fraction of brown dwarfs forms like stars. Thus, young sub-stellar objects might cause HHOs as well. We present selected results of a general survey for HHOs based on DSS-II plates and CCD images taken with the Tautenburg Schmidt telescope. Numerous young objects could be identified due to their association with newly detected HHOs. In some cases the luminosity is consistent with very low-mass stars or close to sub-stellar values. This holds for L1415-IRS and a few infrared sources embedded in other dark clouds (e.g., GF9, BHR111). The question on the minimum mass for outflow activity is addressed.