11 papers
Unraveling Brown Dwarf Origins
Ray Jayawardhana
Brown dwarfs, which occupy a fuzzy gap in mass between stars and planets, appear to be common both in the solar neighborhood and in star-forming regions. Their origin is a topic of…
Close Companions to Nearby Young Stars from Adaptive Optics Imaging on VLT and Keck
Karl E. Haisch, Ray Jayawardhana, Alexis Brandeker +1
We report the results of VLT and Keck adaptive optics surveys of known members of the Eta Chamaeleontis, MBM 12, and TW Hydrae (TWA) associations to search for close companions. Th…
Between Cool Stars and Hot Planets: Origins of Brown Dwarfs
Ray Jayawardhana
Brown dwarfs, which straddle the mass range between stars and planets, appear to be common both in the solar neighborhood and in star-forming regions. Their ubiquity makes the ques…
A Search for Disk Emission in Young Brown Dwarfs: L'-band Observations of sigma Orionis and TW Hydrae
Ray Jayawardhana, David R. Ardila, Beate Stelzer
Studies of disks around young brown dwarfs are of paramount importance to our understanding of the origin, diversity and early evolution of sub-stellar objects. Here we present fir…
T Tauri Stars in the Small Magellanic Cloud
Valentin D. Ivanov, Ray Jayawardhana
The Small Magellanic Cloud (SMC) is an excellent laboratory to study the formation of solar-mass stars in a low-metallicity environment, similar to the conditions expected in the e…
Evolution of Dusty Disks in Nearby Young Stellar Groups
Ray Jayawardhana
Given their proximity and age differences, nearby groups of young stars are valuable laboratories for investigations of disk evolution and diversity. The estimated 10-Myr age of gr…