The minimum Jeans mass, brown dwarf companion IMF, and predictions for detection of Y-type dwarfs

@article{Zuckerman2009TheMJ,
  title={The minimum Jeans mass, brown dwarf companion IMF, and predictions for detection of Y-type dwarfs},
  author={Ben Zuckerman and Inseok Song},
  journal={Astronomy and Astrophysics},
  year={2009},
  volume={493},
  pages={1149-1154}
}
Cool L- and T-type objects were discovered first as companions to stars in 1988 and 1995, respectively. A certain example of the even cooler Y-type spectral class (Teff < 500 K) has not been seen. Recent infrared-imaging observations of stars and brown dwarfs indicate that substellar companions with large semi-major axes and with masses less than the brown dwarf/giant planet dividing line (∼13.5 MJ) are rare. Theoretical considerations of the Jeans mass fragmentation of molecular clouds are… Expand

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References

SHOWING 1-10 OF 74 REFERENCES
Discovery of a cool brown dwarf
TLDR
The discovery of a probable companion to the nearby star G1229, with no more than onetenth the luminosity of the least luminous hydro-gen-burning star, is reported, concluding that the companion is a brown dwarf with a temperature of less than 1,200 K, and a mass ∼20–50 times that of Jupiter. Expand
A low-temperature companion to a white dwarf star
We have discovered an infrared object located about 120 AU from the white dwarf GD165. With the exception of the possible brown dwarf companion to Giclas 29–38 which we reported last year1, theExpand
Discovery of a low-mass brown dwarf companion of the young nearby star G 196-3
TLDR
The separation between the objects and their mass ratio suggest the fragmentation of a collapsing cloud as the most likely origin for G 196-3B, but alternatively it could have originated from a protoplanetary disc that has been dissipated. Expand
Low-Luminosity Companions to White Dwarfs
This paper presents results of a near-infrared imaging survey for low-mass stellar and substellar companions to white dwarfs. A wide-field proper-motion survey of 261 white dwarfs was capable ofExpand
Beyond the t dwarfs: theoretical spectra, colors, and detectability of the coolest brown dwarfs
We explore the spectral and atmospheric properties of brown dwarfs cooler than the latest known T dwarfs. Our focus is on the yet-to-be-discovered free-floating brown dwarfs in the Teff range fromExpand
Hubble Space Telescope NICMOS Observations of T Dwarfs: Brown Dwarf Multiplicity and New Probes of the L/T Transition
We present the results of a Hubble Space Telescope NICMOS imaging survey of 22 T-type field brown dwarfs. Five are resolved as binary systems with angular separations of 0".05-0".35, andExpand
HD 203030B: An Unusually Cool Young Substellar Companion near the L/T Transition
We present the discovery of a brown dwarf companion to the star HD 203030: a G8 V Solar analog with an estimated age between 130 and 400 Myr old G8 V. Separated by 11".9 (487 AU in projection) fromExpand
A new brown dwarf desert? A scarcity of wide ultracool binaries
We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on the Infrared Telescope Facility. We searched a sample of 132 M7-L8 dwarfs toExpand
A companion to AB Pic at the planet/brown dwarf boundary
We report deep imaging observations of the young, nearby star AB Pic, a member of the large Tucana-Horologium association. We have detected a faint, red source $5.5''$ South of the star with JHK Expand
Substellar companions and isolated planetary-mass objects from protostellar disc fragmentation
Self-gravitating protostellar discs are unstable to fragmentation if the gas can cool on a time-scale that is short compared with the orbital period. We use a combination of hydrodynamic simulationsExpand
...
1
2
3
4
5
...