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Observational Clues to Brown Dwarf Origins

Ray Jayawardhana·Subhanjoy Mohanty·Gibor Basri·David R. Ardila·Beate Stelzer·Karl E. Haisch Jr
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Abstract

Over the past year, we have conducted a multi-faceted program to investigate the origin and early evolution of brown dwarfs. Using high-resolution Keck optical spectra of ~30 objects near and below the sub-stellar boundary in several star-forming regions, we present compelling evidence for a T Tauri-like accretion phase in young brown dwarfs. Our systematic study of infrared L'-band (3.8-micron) disk excess in ~50 spectroscopically confirmed young very low mass objects reveal that a significant fraction of brown dwarfs harbor disks at a very young age. Their inner disk lifetimes do not appear to be vastly different from those of disks around T Tauri stars. Taken together, our findings are consistent with a common origin for most low-mass stars, brown dwarfs and isolated planetary mass objects.

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Ray Jayawardhana, Subhanjoy Mohanty, Gibor Basri, David R. Ardila, Beate Stelzer, Karl E. Haisch Jr. 2003-06-11. Observational Clues to Brown Dwarf Origins. https://arxiv.org/abs/astro-ph/0306240

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