The Brown Dwarf — Exoplanet Connection

摘要: Brown dwarfs form like stars but, with masses below 0.075 solar masses, or 1.5 × 1029 kg, they fail to ignite core hydrogen fusion. Lacking a central energy source, cool and fade on timescales that are rapid by astronomical standards. Consequently, the observed characteristics of old, cold brown provide insight into expected properties gas-giant exoplanets. This review focuses as companions main-sequence evolved stars. Following brief historical introduction, we consider different techniques used identify very low mass discuss advantages challenges associated each method. We summarise results from observational programs, particularly those regarding companion frequency function separation, including discussion so-called ‘brown dwarf desert’. implications for planetary formation mechanisms. Finally, outline future surveys companions, direct imaging programs will have sufficient sensitivity detect objects mass.