Brown Dwarfs, Exoplanets, What’s the difference?

Brown dwarfs overlap in effective temperature with giant exoplanets even though they are primarily found in isolation and thought to have formed similar to stars. There is an important class of brown dwarfs that not only overlap in temperature with exoplanets but also in mass and log g. These substellar mass objects differ from exoplanets only in how they formed — or so we think.

In this presentation I will focus on the isolated brown dwarfs, exoplanet companions, and mixed bag of co-moving companions in the ~40 Myr Tucana Horologium association. I will point to the similarities and differences in observable features between populations, and focus on a newly characterized wide system (>200 AU) of a planetary mass companion orbiting a brown dwarf. Using distance calibrated spectral energy distributions and resultant bolometric luminosities and extrapolated effective temperatures, masses, and log g values I will speculate on potential formation scenarios that may have sculpted the isolated “super Jupiters” versus the companion objects.