Results 41 to 50 of about 43,562 (319)
Modeling Brown Dwarfs, L Dwarfs, and T Dwarfs [PDF]
Symposium - International Astronomical Union, 2003 In this contribution, I review a subset of our recent efforts in spectral and opacity modeling aimed at guiding the study of brown dwarfs, L dwarfs, and T dwarfs. I discuss theoretical calculations of the alkali line profiles, newly generated CrH opacities, new evidence for refractory rainout in T dwarfs from optical spectral measurements, and the ...
openaire +3 more sources
Searching for weather in brown dwarfs [PDF]
Monthly Notices of the Royal Astronomical Society, 1999 8 pages, 7 figures. To appear in the Monthly Notices of the RAS.
C. G. Tinney, A. J. Tolley
openaire +3 more sources
The “Mysterious” Origin of Brown Dwarfs [PDF]
The Astrophysical Journal, 2004 11 pages, 3 figures, ApJ submitted Error in equation 1 has been corrected.
Aake Nordlund, Paolo Padoan
openaire +3 more sources
Statistical Properties of Brown Dwarf Companions: Implications for Different Formation Mechanisms [PDF]
, 2013 The mass domain where massive extrasolar planets and brown dwarfs overlap is still poorly understood due to the paucity of brown dwarfs orbiting close to solar-type stars, the so-called brown dwarf desert. In this paper we collect all of available data about close brown dwarfs around solar type stars and their host stars from literature and study the ...
arxiv +1 more source
An irradiated brown-dwarf companion to an accreting white dwarf [PDF]
Nature, 2016 Brown dwarfs and giant planets orbiting close to a host star are subjected to significant irradiation that can modify the properties of their atmospheres. In order to test the atmospheric models that are used to describe these systems, it is necessary to obtain accurate observational estimates of their physical properties (masses, radii, temperatures ...
S. P. Littlefair +10 more
openaire +9 more sources
Searches for brown dwarfs [PDF]
International Astronomical Union Colloquium, 1994 AbstractThis review attempts a brief summary of the numerous and diverse searches for the so-called brown dwarfs, substellar objects having masses between giant planets and the lowest mass M dwarf stars.
openaire +2 more sources
Exploring the Extremes: Characterizing a New Population of Old and Cold Brown Dwarfs
The Astronomical Journal, 2023 Mapping out the populations of thick disk and halo brown dwarfs is important for understanding the metallicity dependence of low-temperature atmospheres and the substellar mass function.
Aaron M. Meisner +5 more
doaj +1 more source
The Substellar Transition Zone: A Stretched Temperature Canyon in Brown Dwarf Population due to Unsteady Hydrogen Fusion [PDF]
, 2018 I summarize results on transitional and degenerate brown dwarfs presented in a series titled Primeval very low-mass stars and brown dwarfs. I introduce an L subdwarf classification scheme, which classified L subdwarfs into three metal subclasses. I would also like to draw your attention to transitional brown dwarfs which have long-lasting unsteady ...
arxiv +1 more source
, 1998 Recent observations of microlensing events in the Large Magellanic Cloud suggest that a sizable fraction of the galactic halo is in the form of Massive Astrophysical Compact Halo Objects (MACHOs). Although the average MACHO mass is presently poorly known, the value $\sim 0.1 M_{\odot}$ looks as a realistic estimate, thereby implying that brown dwarfs ...
DE PAOLIS, Francesco +3 more
openaire +3 more sources
Parallaxes of Brown Dwarfs at USNO [PDF]
Symposium - International Astronomical Union, 2003 Trigonometric parallaxes have been measured by Dahn et al. (2002) for 28 cool dwarfs and brown dwarfs, including 17 L dwarfs and three T dwarfs. Broadband CCD and near-IR photometry (VRIz*JHK) have been obtained for these objects and for 24 additional late-type dwarfs. These data have been supplemented with astrometry and photometry from the literature,
Richard L. Walker +12 more
openaire +3 more sources