Results 1 to 10 of about 238,136 (265)
The Missing Link: Early Methane ("T") Dwarfs in the Sloan Digital Sky Survey [PDF]
Astrophys.J.536:L35-L38,2000, 2000 We report the discovery of three cool brown dwarfs which fall in the effective temperature gap between the latest L dwarfs currently known, with no methane absorption bands in the 1-2.5um range, and the previously known methane (T) dwarfs, whose spectra are dominated by methane and water.
S. K. Leggett +34 more
arxiv +3 more sources
L-dwarf Detection from SDSS Images using Improved Faster R-CNN [PDF]
The Astronomical Journal, 2023 We present a data-driven approach to automatically detect L dwarfs from Sloan Digital Sky Survey (SDSS) images using an improved Faster R-CNN framework based on deep learning.
Zhi Cao +6 more
doaj +2 more sources
Modeling Brown Dwarfs, L Dwarfs, and T Dwarfs [PDF]
arXiv, 2002 In this brief contribution, I touch on a subset of recent efforts in spectral and opacity modeling aimed at improving our understanding 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,
Adam Burrows
arxiv +3 more sources
Infrared Spectroscopy of Brown Dwarfs: the onset of methane absorption in L dwarfs and the L/T transition [PDF]
arXiv, 2001 We present infrared spectra of brown dwarfs with spectral types from mid-L to T. The 0.9-2.5 $\mu$m spectra of three dwarfs found by the Sloan Digital Sky Survey contain absorption bands of both methane and carbon monoxide and bridge the gap between late L and previously observed T dwarfs.
T. R. Geballe +5 more
arxiv +3 more sources
T Dwarf Discoveries by 2MASS [PDF]
arXiv, 2001 Over a dozen T dwarfs, brown dwarfs that exhibit methane absorption features at 1.6 and 2.2 $\micron$, have been discovered by the 2MASS survey. We discuss how the search for these objects has been made, point out some of the limitations of using near-infrared data to find the warmest T dwarfs, and highlight a few of the more interesting T dwarfs that ...
Adam J. Burgasser
arxiv +3 more sources
Near-Infrared Photometry and Spectroscopy of L and T Dwarfs: the Effects of Temperature, Clouds, and Gravity [PDF]
Astron.J.127:3553,2004, 2004 We present JHK photometry and spectroscopy for a sample of newly identified L and T dwarfs from the Sloan Digital Sky Survey (SDSS) and known dwarfs from the SDSS and the Two Micron All Sky Survey (2MASS). Spectral classification has been carried out using four infrared indices; we identify 9 new L8-9.5 dwarfs and 14 new T dwarfs from SDSS, including ...
G. R. Knapp +28 more
arxiv +3 more sources
Redder than Red: Discovery of an Exceptionally Red L/T Transition Dwarf
The Astrophysical Journal Letters, 2023 We present the discovery of CWISE J050626.96+073842.4 (CWISE J0506+0738), an L/T transition dwarf with extremely red near-infrared colors discovered through the Backyard Worlds: Planet 9 citizen science project. Photometry from UKIRT and CatWISE give a (
Adam C. Schneider +26 more
doaj +1 more source
Early Results from GLASS-JWST. XIII. A Faint, Distant, and Cold Brown Dwarf
The Astrophysical Journal Letters, 2023 We present the serendipitous discovery of a late T-type brown dwarf candidate in JWST NIRCam observations of the Early Release Science Abell 2744 parallel field.
Mario Nonino +20 more
doaj +1 more source
Astrometry and Photometry for ≈1000 L, T, and Y Dwarfs from the UKIRT Hemisphere Survey
The Astronomical Journal, 2023 We present the positions, proper motions, and near-infrared photometry for 966 known objects with spectral types later than M that were observed as part of the the UKIRT Hemisphere Survey (UHS).
Adam C. Schneider +7 more
doaj +1 more source
The Astronomical Journal, 2023 We present three new brown dwarf spectral-binary candidates: CWISE J072708.09−360729.2, CWISE J103604.84−514424.4, and CWISE J134446.62−732053.9, discovered by citizen scientists through the Backyard Worlds: Planet 9 project.
Alexia Bravo +11 more
doaj +1 more source