Related papers: On the Formation of Brown Dwarfs
Although many models have been proposed, the physical mechanisms responsible for the formation of low-mass brown dwarfs are poorly understood. The multiplicity properties and minimum mass of the brown-dwarf mass function provide critical…
I discuss the role that disc fragmentation plays in the formation of gas giant and terrestrial planets, and how this relates to the formation of brown dwarfs and low-mass stars, and ultimately to the process of star formation. Protostellar…
We have undertaken a series of hydrodynamic + N-body simulations in order to explore the properties of young stars. Our results suggest that the IMF may be sensitive to environment in its substellar region, with more brown dwarfs being…
After decades of brown dwarf discovery and follow-up, we can now infer the functional form of the mass distribution within 20 parsecs, which serves as a constraint on star formation theory at the lowest masses. Unlike objects on the main…
Brown dwarfs and very low mass stars are a significant fraction of stars in our galaxy, and they are interesting laboratories to investigate planet formation in extreme conditions of low temperature and densities. In addition, the dust…
There is evidence that stars and browns dwarfs grow through episodic rather than continuous gas accretion. However, the role of episodic accretion in the formation of brown dwarfs remains mostly unexplored. We investigate the role of…
Brown Dwarfs (BDs) are crucial objects in our understanding of both star and planet formation. However, there is still an unconcluded debate about which is the dominant formation mechanism of these objects. For this, it is mandatory to…
Planets have been detected around a variety of stars, including low-mass objects, such as brown dwarfs. However, such extreme cases are challenging for planet formation models. Recent sub-millimeter observations of disks around brown dwarf…
The onset of planet formation in protoplanetary disks is marked by the growth and crystallization of sub-micron-sized dust grains accompanied by dust settling toward the disk mid-plane. Here we present infrared spectra of disks around brown…
Recent surveys have identified sub-stellar objects down to planetary masses in nearby star-forming regions. Reliable determination of the disk frequency in young brown dwarfs is of paramount importance to understanding their origin. Here we…
We suggest that planets, brown dwarfs, and even low mass stars can be formed by fragmentation of protoplanetary disks around very massive stars M>~100 solar masses. We discuss how fragmentation conditions make the formation of very massive…
Surveys of young star-forming regions have discovered a growing population of planetary-mass (<13 M_Jup) companions around young stars. There is an ongoing debate as to whether these companions formed like planets (that is, from the…
We examine the spatial distribution of brown dwarfs produced by the decay of small-N stellar systems as expected from the embryo ejection scenario. We model a cluster of several hundred stars grouped into 'cores' of a few stars/brown…
The protostellar outflow mechanism operates for a significant fraction of the pre-main sequence phase of a solar mass star and is thought to have a key role in star and perhaps even planet formation. This energetic mechanism manifests…
We present the stellar and substellar mass function of the open cluster IC2391, plus its radial dependence, and use this to put constraints on the formation mechanism of brown dwarfs. Our multiband optical and infrared photometric survey…
We explore the possibility that, in the vicinity of an OB star, a prestellar core which would otherwise have formed an intermediate or low-mass star may form a free-floating brown dwarf or planetary-mass object, because the outer layers of…
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…
Giant planets and brown dwarfs play a crucial role in star and planet formation, as they are situated at the boundary between planets and stars with uncertain formation mechanisms. Previous observational searches for the formation boundary…
In this review, we examine the successes and weaknesses of modern low-mass star and brown dwarf theory.(1) We first focus on the mechanical (equation of state) and thermal (atmosphere) properties and on the evolution. We then examine the…
The physics of brown dwarfs has continuously improved since the discovery of these astrophysical bodies. The first important developments were devoted to the description of their mechanical structure, with the derivation of an appropriate…