The formation of brown dwarfs

Abstract

We review four mechanisms for forming brown dwarfs: (i) turbulent fragmentation (producing very low-mass prestellar cores); (ii) gravitational instabilities in discs; (iii) dynamical ejection of stellar embryos from their placental cores; and (iv) photo-erosion of pre-existing cores in HII regions. We argue (a) that these are simply the mechanisms of low-mass star formation, and (b) that they are not mutually exclusive. If, as seems possible, all four mechanisms operate in nature, their relative importance may eventually be constrained by their ability to reproduce the binary statistics of brown dwarfs, but this will require fully 3-D radiative magneto-hydrodynamic simulations.

7 pages, 1 figure. To appear in Astron.Nachrichten. Includes an.cls file

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Cited by in corpus (6)

• Candidate free-floating super-Jupiters in the young sigma Orionis open cluster
• Proper motion L and T dwarf candidate members of the Pleiades
• The low-mass population of the Rho Ophiuchi molecular cloud
• Substellar Objects in Nearby Young Clusters (SONYC) III: Chamaeleon-I
• Discovery of a widely separated UCD-WD binary
• Deep near-IR observations of the Globular Cluster M4: Hunting for Brown Dwarfs