WISEA J153429.75−104303.3 (a.k.a. “The Accident”) is a brown dwarf with unique observational properties unlike those of any other known (sub)stellar object. It is thought to be a very cold, metal-poor brown dwarf, and potentially the first identified Y-type subdwarf. Although WISEA J153429.75−104303.3 is extremely faint at
Exploring the Extremes: Characterizing a New Population of Old and Cold Brown Dwarfs
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. Recently, a new population of cold and metal-poor brown dwarfs has been discovered, with
- NSF-PAR ID:
- 10431350
- Publisher / Repository:
- DOI PREFIX: 10.3847
- Date Published:
- Journal Name:
- The Astronomical Journal
- Volume:
- 166
- Issue:
- 2
- ISSN:
- 0004-6256
- Page Range / eLocation ID:
- Article No. 57
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract λ ∼ 1.25μ m, low-temperature atmosphere models suggest thatY -band flux could increase dramatically relative toJ -band as metallicity decreases from solar. We therefore obtained deepY -band follow-up imaging of WISEA J153429.75−104303.3 with the Dark Energy Camera, and report a resultingY -band limit ofY > 21.79 mag (Vega, 5σ ). -
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