Results 41 to 50 of about 15,774,260 (349)
The Viewing Geometry of Brown Dwarfs Influences Their Observed Colors and Variability Amplitudes [PDF]
, 2017 In this paper we study the full sample of known Spitzer [3.6 μm] and J-band variable brown dwarfs. We calculate the rotational velocities, , of 16 variable brown dwarfs using archival Keck NIRSPEC data and compute the inclination angles of 19 variable ...
J. Vos, K. Allers, B. Biller
semanticscholar +1 more source
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 +2 more sources
IZphotometry of L dwarfs and the implications for brown dwarf surveys [PDF]
Monthly Notices of the Royal Astronomical Society, 2000 The I-Z colour has been recently shown to be a good temperature indicator for M dwarfs. We present the first IZ photometry of a small sample of L dwarfs ranging in spectral type from L0.5V to L6.0V. We find that the I-Z colour is not a good temperature indicator for objects between L1V and L5V, such objects having colours that overlap with mid M dwarfs.
Steele, I. A., Howells, L.
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DA white dwarfs in Sloan Digital Sky Survey Data Release 7 and a search for infrared excess emission [PDF]
, 2011 We present a method which uses colour–colour cuts on the Sloan Digital Sky Survey (SDSS) photometry to select white dwarfs with hydrogen-rich (DA) atmospheres without the recourse to spectroscopy.
Farihi, J. +19 more
core +1 more source
K2 Ultracool Dwarfs Survey. I. Photometry of an L Dwarf Superflare [PDF]
The Astrophysical Journal, 2017 Abstract We report on K2 Campaign 8 measurements of a huge white light flare on the L1 dwarf SDSSp J005406.55-003101.8 (EPIC 220186653). The source is a typical L1 dwarf at a distance of ∼50 pc, probably an old hydrogen-burning star rather than a young brown dwarf.
John E. Gizis +4 more
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Binaries and the L Dwarf/T Dwarf Transition [PDF]
The Astrophysical Journal, 2007 51 pages, 14 figures; accepted for publication in ...
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Parallaxes of L and T dwarfs [PDF]
Proceedings of the International Astronomical Union, 2004 We discuss a new program to measure the parallaxes of a number of L and T dwarfs, objects that bridge the gap between M dwarfs and planets. This pilot project tests the feasibility of using large telescopes with infrared detectors to determine parallaxes at the level of milli-arcseconds (mas). First results show that we are able to achieve the required
R. L. Smart +2 more
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Primeval very low-mass stars and brown dwarfs – IV. New L subdwarfs, Gaia astrometry, population properties, and a blue brown dwarf binary [PDF]
Monthly notices of the Royal Astronomical Society, 2018 We present 27 new L subdwarfs and classify five of them as esdL and 22 as sdL. Our L subdwarf candidates were selected with the UKIRT Infrared Deep Sky Survey and Sloan Digital Sky Survey. Spectroscopic follow-up was carried out primarily with the OSIRIS
Z. Zhang +21 more
semanticscholar +1 more source
Spectroscopy of Hyades L dwarf candidates★ [PDF]
Monthly Notices of the Royal Astronomical Society, 2014 12 pages, 7 figures, 3 tables; accepted for publication in ...
Lodieu, N., Boudreault, S., Béjar, V.
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THE FIRST HUNDRED BROWN DWARFS DISCOVERED BY THE WIDE-FIELD INFRARED SURVEY EXPLORER (WISE) [PDF]
, 2011 We present ground-based spectroscopic verification of 6 Y dwarfs (see also Cushing et al.), 89 T dwarfs, 8 L dwarfs, and 1 M dwarf identified by the Wide-field Infrared Survey Explorer (WISE). Eighty of these are cold brown dwarfs with spectral types ⩾T6,
J. Kirkpatrick +39 more
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