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arXiv · 2302.12723

JWST Observations of the Enigmatic Y Dwarf WISE 1828+2650: I. Limits to a Binary Companion

Matthew De Furio·Ben W. Lew·Charles A. Beichman·Thomas Roellig·Geoffrey Bryden·David R. Ciardi·Michael R. Meyer·Marcia J. Rieke·Alexandra Z. Greenbaum·Jarron Leisenring·Jorge Llop-Sayson·Marie Ygouf·Loïc Albert·Martha L. Boyer·Daniel J. Eisenstein·Klaus W. Hodapp·Scott Horner·Doug Johnstone·Douglas M. Kelly·Karl A. Misselt·George H. Rieke·John A. Stansberry·Erick T. Young
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Abstract

The Y-dwarf WISE 1828+2650 is one of the coldest known Brown Dwarfs with an effective temperature of $\sim$300 K. Located at a distance of just 10 pc, previous model-based estimates suggest WISE1828+2650 has a mass of $\sim$5-10 Mj, making it a valuable laboratory for understanding the formation, evolution and physical characteristics of gas giant planets. However, previous photometry and spectroscopy have presented a puzzle with the near-impossibility of simultaneously fitting both the short (0.9-2.0 microns) and long wavelength (3-5 microns) data. A potential solution to this problem has been the suggestion that WISE 1828+2650 is a binary system whose composite spectrum might provide a better match to the data. Alternatively, new models being developed to fit JWST/NIRSpec and MIRI spectroscopy might provide new insights. This article describes JWST/NIRCam observations of WISE 1828+2650 in 6 filters to address the binarity question and to provide new photometry to be used in model fitting. We also report Adaptive Optics imaging with the Keck 10 m telescope. We find no evidence for multiplicity for a companion beyond 0.5 AU with either JWST or Keck. Companion articles will present low and high resolution spectra of WISE 1828+2650 obtained with both NIRSpec and MIRI.

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Matthew De Furio, Ben W. Lew, Charles A. Beichman, Thomas Roellig, Geoffrey Bryden, David R. Ciardi, Michael R. Meyer, Marcia J. Rieke, Alexandra Z. Greenbaum, Jarron Leisenring, Jorge Llop-Sayson, Marie Ygouf, Loïc Albert, Martha L. Boyer, Daniel J. Eisenstein, Klaus W. Hodapp, Scott Horner, Doug Johnstone, Douglas M. Kelly, Karl A. Misselt, George H. Rieke, John A. Stansberry, Erick T. Young. 2023-02-24. JWST Observations of the Enigmatic Y Dwarf WISE 1828+2650: I. Limits to a Binary Companion. https://doi.org/10.3847/1538-4357%2Facbf1e

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