Results 1 to 10 of about 3,488 (245)

Redder than Red: Discovery of an Exceptionally Red L/T Transition Dwarf [PDF]

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, Adam J. Burgasser, Justice Bruursema, Jeffrey A. Munn, Frederick J. Vrba, Dan Caselden, Martin Kabatnik, Austin Rothermich, Arttu Sainio, Thomas P. Bickle, Scott E. Dahm, Aaron M. Meisner, J. Davy Kirkpatrick, Genaro Suárez, Jonathan Gagné, Jacqueline K. Faherty, Johanna M. Vos, Marc J. Kuchner, Stephen J. Williams, Daniella Bardalez Gagliuffi, Christian Aganze, Chih-Chun Hsu, Christopher Theissen, Michael C. Cushing, Federico Marocco, Sarah Casewell, The Backyard Worlds: Planet 9 Collaboration   +26 more
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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, Karl Glazebrook, Adam J. Burgasser, Gianluca Polenta, Takahiro Morishita, Marius Lepinzan, Marco Castellano, Adriano Fontana, Emiliano Merlin, Andrea Bonchi, Diego Paris, Tommaso Treu, Benedetta Vulcani, Xin Wang, Paola Santini, Eros Vanzella, Themiya Nanayakkara, Amata Mercurio, Piero Rosati, Claudio Grillo, Marusa Bradac   +20 more
doaj   +1 more source

An Investigation of New Brown Dwarf Spectral Binary Candidates From the Backyard Worlds: Planet 9 Citizen Science Initiative

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, Adam C. Schneider, Daniella Bardalez Gagliuffi, Adam J. Burgasser, Aaron M. Meisner, J. Davy Kirkpatrick, Jacqueline K. Faherty, Marc J. Kuchner, Dan Caselden, Arttu Sainio, Les Hamlet, The Backyard Worlds: Planet 9 Collaboration   +11 more
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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, Jeffrey A. Munn, Frederick J. Vrba, Justice Bruursema, Scott E. Dahm, Stephen J. Williams, Michael C. Liu, Bryan N. Dorland   +7 more
doaj   +1 more source

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, S. K. Leggett, Sarah E. Logsdon, Adam C. Schneider, Pascal Tremblin, Mark Phillips   +5 more
doaj   +1 more source

Little Red Dots or Brown Dwarfs? NIRSpec Discovery of Three Distant Brown Dwarfs Masquerading as NIRCam-selected Highly Reddened Active Galactic Nuclei

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
doaj   +1 more source

Stellar equilibrium configurations of white dwarfs in the f(R, T) gravity

European Physical Journal C: Particles and Fields, 2017
In this work we investigate the equilibrium configurations of white dwarfs in a modified gravity theory, namely, f(R, T) gravity, for which R and T stand for the Ricci scalar and trace of the energy-momentum tensor, respectively.
G. A. Carvalho, R. V. Lobato, P. H. R. S. Moraes, José D. V. Arbañil, E. Otoniel, R. M. Marinho, M. Malheiro   +6 more
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L-dwarf Detection from SDSS Images using Improved Faster R-CNN

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, Zhenping Yi, Jingchang Pan, Hao Su, Yude Bu, Xiao Kong, Ali Luo   +6 more
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The First Y Dwarf Data from JWST Show that Dynamic and Diabatic Processes Regulate Cold Brown Dwarf Atmospheres

The Astrophysical Journal, 2023
The James Webb Space Telescope (JWST) is now observing Y dwarfs, the coldest known brown dwarfs, with effective temperatures T _eff ≲ 475 K. The first published observations provide important information: not only is the atmospheric chemistry out of ...
S. K. Leggett, Pascal Tremblin
doaj   +1 more source

WIYN Open Cluster Study 89. M48 (NGC 2548) 2: Lithium Abundances in the 420 Myr Open Cluster M48 from Giants through K Dwarfs

The Astrophysical Journal, 2023
We consider WIYN/Hydra spectra of 329 photometric candidate members of the 420 Myr old open cluster M48 and report lithium detections or upper limits for 234 members and likely members.
Qinghui Sun, Constantine P. Deliyannis, Aaron Steinhauer, Barbara J. Anthony-Twarog, Bruce A. Twarog   +4 more
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