Astronomy and astrophysics

Unraveling the Origins of Brown Dwarfs

by Ray Jayawardhana (University of Toronto)

Europe/Stockholm
FA 31

FA 31

Description
With the identification of hundreds of brown dwarfs in the solar neighborhood and young clusters, the origin of sub-stellar objects has become a topic of widespread interest. Infrared and millimeter detections of dusty disks as well as spectroscopic signatures of gas accretion and outflow suggest that young brown dwarfs undergo a T Tauri phase, possibly implying a common formation mechanism with Sun-like stars. Binary properties provide another important diagnostic of brown dwarf origin: while binary frequency and maximum separation appear to be low in the sub-stellar regime, recent observations have revealed a number of wide pairs, posing a challenge to some formation models. Now we are able to extend studies of disks and binarity to young planetary mass objects, which are found both in isolation and as companions. Remarkably, the star formation process seems to be capable of producing planetary mass objects directly.