The Formation of Brown Dwarfs - Fundamental properties of very young objects near and below the substellar limit
نویسنده
چکیده
3 1 Brown dwarfs – an introduction 5 1.1 Brown dwarfs: objects between stars and planets . . . . . . . . . . 5 1.2 Formation models . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.2.1 Planet-like formation . . . . . . . . . . . . . . . . . . . . . 8 1.2.2 Star-like formation . . . . . . . . . . . . . . . . . . . . . . 10 1.3 Substellar evolution . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.3.1 Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.3.2 Evolutionary models . . . . . . . . . . . . . . . . . . . . . 16 1.4 Atmospheres, spectra and weather phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . 18 1.4.1 Atmospheres and spectra . . . . . . . . . . . . . . . . . . . 18 1.4.2 Condensation, clouds and weather . . . . . . . . . . . . . . 19 1.5 Magnetic activity . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 1.6 Substellar tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 1.6.1 The lithium test . . . . . . . . . . . . . . . . . . . . . . . . 24 1.6.2 Methane test . . . . . . . . . . . . . . . . . . . . . . . . . 26 1.6.3 Substellar test by mass determination . . . . . . . . . . . . 26 1.7 Multiplicity and circumstellar material . . . . . . . . . . . . . . . 26
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