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Title: Thirteen New M Dwarf + T Dwarf Pairs Identified with WISE/NEOWISE
Abstract We present the discovery of 13 new widely separated T dwarf companions to M dwarf primaries, identified using Wide-field Infrared Survey Explorer/NEOWISE data by the CatWISE and Backyard Worlds: Planet 9 projects (hereafter BYW). This sample represents an ∼60% increase in the number of known M + T systems, and allows us to probe the most extreme products of binary/planetary system formation, a discovery space made available by the CatWISE2020 catalog and the BYW effort. Highlights among the sample are WISEP J075108.79-763449.6, a previously known T9 thought to be old due to its spectral energy distribution, which was found by Zhang et al. (2021b) to be part of a common proper motion pair with L34-26 A, a well-studied young M3 V star within 10 pc of the Sun; CWISE J054129.32-745021.5 B and 2MASS J05581644-4501559 B, two T8 dwarfs possibly associated with the very fast-rotating M4 V stars CWISE J054129.32745021.5 A and 2MASS J05581644-4501559 A; and UCAC3 52-1038 B, which is among the widest late-T companions to main-sequence stars, with a projected separation of ∼7100 au. The new benchmarks presented here are prime JWST targets, and can help us place strong constraints on the formation and evolution theory of substellar objects as well as on atmospheric models for these cold exoplanet analogs.  more » « less
Award ID(s):
2009136 2009177
PAR ID:
10533771
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Corporate Creator(s):
Publisher / Repository:
IOP
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
967
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
147
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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