Results 21 to 30 of about 222,937 (306)
The Astronomical Journal, 2000 We present spectroscopic, photometric and astrometric observations of four bright L dwarfs identified in the course of the 2MASS near-infrared survey. Our spectroscopic data extend to wavelengths shortward of 5000 in the L0 dwarf 2MASSJ0746+2000 and the L4 dwarf 2MASSJ0036+1840, allowing the identification of absorption bands due to MgH and CaOH.
Rik J. Williams +7 more
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The Astrophysical Journal Letters, 2023 We report direct observational evidence for a latitudinal dependence of dust cloud opacity in ultracool dwarfs, indicating that equatorial latitudes are cloudier than polar latitudes.
Genaro Suárez +4 more
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L and T Dwarf Models and the L to T Transition [PDF]
The Astrophysical Journal, 2006 accepted to the Astrophysical Journal, 21 figures (20 in color); spectral models in electronic form available at http://zenith.as.arizona.edu ...
David Sudarsky +2 more
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Mathematical Biosciences and Engineering, 2023 We consider the boundary value problem of finite beam deflection on elastic foundation with two point boundary conditions of the form $ u^{(p)}(-l) = u^{(q)}(-l) = u^{(r)}(l) = u^{(s)}(l) = 0 $, $ p < q $, $ r < s $, which we call elementary.
Sung Woo Choi
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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
Coryn A. L. Bailer-Jones +2 more
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Massive white dwarfs in $$f(\mathtt {R,L_m})$$ f ( R , L m ) gravity
European Physical Journal C: Particles and Fields, 2022 In this work, we investigate the equilibrium configurations of massive white dwarfs (MWD) in the context of modified gravity, namely $$f(\mathtt {R,L_m})$$ f ( R , L m ) gravity, where $$\mathtt {R}$$ R stands for the Ricci scalar and $$\mathtt {L_m}$$ L
R. V. Lobato +3 more
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[ITAL]L[/ITAL]-Band Photometry of L and T Dwarfs [PDF]
The Astrophysical Journal, 2001 We present K- and L-band photometry obtained with the Keck I telescope for a representative sample of L and T dwarfs. These observations were motivated in part by the dominant role water and methane play in shaping the flux near 2 and 3 microns and by the potential use of these bands as indicators of spectral class in the infrared.
Nancy J. Chanover +4 more
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A SURVEY FOR Hα EMISSION FROM LATE L DWARFS AND T DWARFS* [PDF]
The Astrophysical Journal, 2016 ABSTRACT Recently, studies of brown dwarfs have demonstrated that they possess strong magnetic fields and have the potential to produce radio and optical auroral emissions powered by magnetospheric currents. This emission provides the only window on magnetic fields in the coolest brown dwarfs and identifying additional benchmark objects ...
Pineda, J +5 more
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Clouds, Brightening and Multiplicity Across the L Dwarf∕T Dwarf Transition [PDF]
AIP Conference Proceedings, 2009 The transition between the two lowest-luminosity spectral classes of brown dwarfs--the L dwarfs and T dwarfs--is traversed by nearly all brown dwarfs as they cool over time. Yet distinct features of this transition, such as the "J-band bump" and an unusually high rate of multiplicity, remain outstanding problems, although evidence points to condensate ...
Adam J. Burgasser, Eric Stempels
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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 ...
S. Boudreault +6 more
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