Results 11 to 20 of about 66 (62)

Discovery of CWISE J052306.42−015355.4, an Extreme T Subdwarf Candidate [PDF]

The Astronomical Journal, 2022
Abstract We present the discovery of CWISE J052306.42−015355.4, which was found as a faint, significant proper-motion object (0.″52 ± 0.″08 yr−1) using machine-learning tools on the unWISE re-processing of time series images from the Wide-field Infrared Survey Explorer.
Brooks, Hunter, Kirkpatrick, J. Davy, Caselden, Dan, Schneider, Adam C., Meisner, Aaron M., Faherty, Jacqueline K., Casewell, S. L., Kuchner, Marc J., Worlds, The Backyard, Collaboration, Planet 9   +9 more
openaire   +6 more sources

WISEA J041451.67–585456.7 and WISEA J181006.18–101000.5: The First Extreme T-type Subdwarfs? [PDF]

The Astrophysical Journal, 2020
Abstract We present the discoveries of WISEA J041451.67−585456.7 and WISEA J181006.18−101000.5, two low-temperature (1200–1400 K), high proper motion T-type subdwarfs. Both objects were discovered via their high proper motion (>0.″5 yr−1); WISEA J181006.18−101000.5 as part of the NEOWISE proper motion survey and WISEA J041451.67 ...
Schneider, Adam C., Burgasser, Adam J., Gerasimov, Roman, Marocco, Federico, Gagne, Jonathan, Goodman, Sam, Beaulieu, Paul, Pendrill, William, Rothermich, Austin, Sainio, Arttu, Kuchner, Marc J., Caselden, Dan, Meisner, Aaron M., Faherty, Jacqueline K., Mamajek, Eric E., Hsu, Chih-Chun, Greco, Jennifer J., Cushing, Michael C., Kirkpatrick, J. Davy, Gagliuffi, Daniella Bardalez, Logsdon, Sarah E., Allers, Katelyn, Debes, John H., Worlds, The Backyard, Collaboration, Planet 9   +24 more
openaire   +3 more sources

Discovery of a Possible Early-T Thick-disk Subdwarf from the AllWISE2 Motion Survey* [PDF]

The Astronomical Journal, 2018
Abstract We have discovered a potential T0 ± 1 subdwarf from a search for sources in the AllWISE2 Motion Survey that do not have counterparts in surveys at shorter wavelengths. With a tangential velocity of ∼170 km s−1, this object—WISE J071121.36–573634.2—has kinematics that are consistent with the thick-disk population of the Milky Way.
Kendra Kellogg, J. Davy Kirkpatrick, Stanimir Metchev, Jonathan Gagné, Jacqueline K. Faherty   +4 more
openaire   +3 more sources

JWST/NIRSpec Spectral Standards for M, L, and T Dwarfs and Subdwarfs

Research Notes of the AAS
Abstract We present low-resolution infrared spectral standards in the 0.76–5.0  μ m range based on JWST NIRspec Prism data from deep sky surveys. Our standards encompass spectral types M, L, and T, and dwarf and subdwarf metallicity classes. The standards extend ground-based
Evan Pritchard, Marylin Loritsch, Julia Haynes, Sara Morrissey, Emma Softich, Adam J. Burgasser   +5 more
openaire   +2 more sources

Ultracool Subdwarfs: Metal-poor Stars and Brown Dwarfs Extending into the Late-type M, L and T Dwarf Regimes

, 2004
Recent discoveries from red optical proper motion and wide-field near-infrared surveys have uncovered a new population of ultracool subdwarfs -- metal-poor stars and brown dwarfs extending into the late-type M, L and possibly T spectral classes. These objects are among the first low-mass stars and brown dwarfs formed in the Galaxy, and are valuable ...
Burgasser, Adam J., Kirkpatrick, J. Davy, Lepine, Sebastien   +2 more
openaire   +2 more sources

K _s -band Photometry of the Extreme T Subdwarf CWISE J221706.28−145437.6*

Research Notes of the AAS
Abstract We present deep K s -band imaging of the extreme T subdwarf CWISE J221706.28−145437.6. Using the new photometry, we construct its spectral energy distribution and find this object exhibits exceptionally strong collision-induced absorption in the H and K band.
Jerry J.-Y. 俊䶮 Zhang 章, Nicolas Lodieu, Eduardo L. Martín   +2 more
openaire   +2 more sources

High Proper Motion Discoveries from the UKIRT Hemisphere Survey

The Astronomical Journal
We used the third data release of the UKIRT Hemisphere Survey to locate previously unrecognized high proper motion objects. We identify a total of 127 new discoveries with total proper motions ≳300 mas yr ^−1 .
Wings Zhang, Adam C. Schneider, Thomas P. Bickle, Adam J. Burgasser, Emma Softich, Federico Marocco, Daniella Bardalez Gagliuffi, Jacqueline K. Faherty, Aaron M. Meisner, J. Davy Kirkpatrick, Marc J. Kuchner, Martin Kabatnik, Frank Kiwy, Arttu Sainio, Jörg Schümann, Karl Selg-Mann, Nikolaj Stevnbak Andersen, Bruce Baller, Paul Beaulieu, John Bell, Dan Caselden, Guillaume Colin, Alexandru Dereveanco, Christoph Frank, Konstantin Glebov, Léopold Gramaize, Leslie K. Hamlet, David W. Martin, William Pendrill, Stéphane Perlin, Andres Stenner, Christopher Tanner, Melina Thévenot, Vinod Thakur   +33 more
doaj   +1 more source

Brown Dwarf Candidates in the JADES and CEERS Extragalactic Surveys

The Astrophysical Journal
By combining the James Webb Space Telescope (JWST)/NIRCam JADES and CEERS extragalactic data sets, we have uncovered a sample of 21 T and Y brown dwarf candidates at best-fit distances between 0.1 and 4.2 kpc. These sources were selected by targeting the
Kevin N. Hainline, Jakob M. Helton, Benjamin D. Johnson, Fengwu Sun, Michael W. Topping, Jarron M. Leisenring, William M. Baker, Daniel J. Eisenstein, Ryan Hausen, Raphael E. Hviding, Jianwei Lyu, Brant Robertson, Sandro Tacchella, Christina C. Williams, Christopher N. A. Willmer, Thomas L. Roellig   +15 more
doaj   +1 more source

Observations of the Ultraviolet-bright Star III-60 in the Globular Cluster NGC 6723

The Astrophysical Journal
We have analyzed archival far-ultraviolet spectra of the UV-bright star III-60 in the globular cluster NGC 6723 obtained with the Far Ultraviolet Spectroscopic Explorer and the Cosmic Origins Spectrograph. We find that the star's photospheric parameters (
William V. Dixon
doaj   +1 more source

Parallaxes, Proper Motions, and Near-infrared Photometry for 173 L and T Dwarfs from the US Naval Observatory Infrared Astrometry Program

The Astrophysical Journal
We present near-infrared parallax and proper motion astrometry for 74 L dwarfs and 99 T dwarfs, as single objects or in binary systems, obtained with the ASTROCAM astrometric imager on the USNO, Flagstaff Station 1.55 m telescope over two observing ...
Frederick J. Vrba, Adam C. Schneider, Jeffrey A. Munn, Arne A. Henden, Christain B. Luginbuhl, Conard C. Dahn, Harry H. Guetter, Blaise J. Canzian, Trudy M. Tilleman, Scott E. Dahm, Stephen J. Williams, Justice E. Bruursema, J. Davy Kirkpatrick, Adam J. Burgasser   +13 more
doaj   +1 more source