Results 31 to 40 of about 71,830 (288)
A Uniform Retrieval Analysis of Ultra-cool Dwarfs. III. Properties of Y Dwarfs [PDF]
The Astrophysical Journal, 2019 Abstract Ultra-cool brown dwarfs offer a unique window into understanding substellar atmospheric physics and chemistry. Their strong molecular absorption bands at infrared wavelengths, Jupiter-like radii, cool temperatures, and lack of complicating stellar irradiation make them ideal test beds for understanding Jovian-like atmospheres ...
Joseph A. Zalesky +3 more
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CFBDS J005910.90-011401.3: reaching the T-Y Brown Dwarf transition? [PDF]
Astronomy & Astrophysics, 2008 We report the discovery of CFBDS J005910.90-011401.3 (hereafter CFBDS0059), the coolest brown dwarf identified to date. We found CFBDS0059 using i' and z' images from the Canada-France-Hawaii Telescope (CFHT), and present optical and near-infrared photometry, Keck laser guide star adaptive optics imaging, and a complete near-infrared spectrum, from 1.0
P. Delorme +11 more
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Atmospheric Habitable Zones in Y Dwarf Atmospheres [PDF]
The Astrophysical Journal, 2017 Abstract We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life. To illustrate our model, we use a cool Y dwarf atmosphere, such as WISE J085510.83–0714442.5, whose 4.5–5.2
Jack S. Yates +3 more
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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
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Y Gem: A White Dwarf Symbiotic Star?
The Astrophysical Journal, 2022 Abstract In this work we conduct a thorough investigation of the X-ray and ultraviolet (UV) properties of Y Gem based on six archival XMM-Newton and Chandra observations to explore the nature of the system. The results show that Y Gem has strong (1032–34 erg s−1) X-ray emission, including a hard (with a maximum emission temperature of 8 ...
Zhuo-li Yu +4 more
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The Astrophysical Journal Letters, 2023 Cold, substellar objects such as brown dwarfs have long been recognized as contaminants in color-selected samples of active galactic nuclei (AGNs). In particular, their near- to mid-infrared colors (1–5 μ m) can closely resemble the V-shaped ( f _λ ...
Danial Langeroodi, Jens Hjorth
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NEGLECTED CLOUDS IN T AND Y DWARF ATMOSPHERES [PDF]
The Astrophysical Journal, 2012 17 pages, 12 figures, Accepted for publication in ...
Morley, Caroline V. +5 more
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Searching for Photometric Variability across the L, T & Y Dwarf Sequence [PDF]
Proceedings of the International Astronomical Union, 2013 AbstractTo investigate the atmospheres of ultracool brown dwarfs with temperatures covering the range of transiting and directly imaged planets, we have monitored a sample of 76 L, T and Y brown dwarfs for infrared photometric variability. This survey was conducted in the J-band using both the SOFI camera on the 3.5-m NTT and the SWIRC camera on the 6 ...
Abhijith Rajan +4 more
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SEARCHING FOR BINARY Y DWARFS WITH THE GEMINI MULTI-CONJUGATE ADAPTIVE OPTICS SYSTEM (GeMS) [PDF]
The Astrophysical Journal, 2016 ABSTRACT The NASA Wide-field Infrared Survey Explorer (WISE) has discovered almost all the known members of the new class of Y-type brown dwarfs. Most of these Y dwarfs have been identified as isolated objects in the field. It is known that binaries with L- and T-type brown dwarf primaries are less prevalent than either M-dwarf or solar-
Daniela Opitz +5 more
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GTC OSIRISz-band imaging of Y dwarfs [PDF]
Astronomy & Astrophysics, 2013 The aim of the project is to contribute to the characterisation of the spectral energy distribution of the coolest brown dwarfs discovered to date, the Y dwarfs. We obtained z-band far-red imaging for six Y dwarfs and a T9+Y0 binary with the OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) instrument on the 10.4-m Gran ...
Lodieu, N., Bejar, V. J. S., Rebolo, R.
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