Eight New Substellar Hyades Candidates from the UKIRT Hemisphere Survey

• DOI: 10.48550/arxiv.2408.10112
• Publication Date: 2024-08-19
• Authors: Adam C. Schneider; Michael C. Cushing; Robert A. Stiller; Jeffrey A. Munn; F. J. Vrba; Justice Bruursema; Stephen J. Williams; Michael C. Liu; A. Bravo; Jacqueline K. Fah...; Austin Rothermich; Emily Calamari; Dan Caselden; Martin Kabatnik; Arttu Sainio; Thomas P. Bickle; William Pendrill; Nikolaj Stevnbak ...; Melina Thévenot
• Keywords: Open star clusters; Brown dwarfs; Astrophysics - Solar and Stellar Astrophysics; Astronomy; Astrophysics of Galaxies (astro-ph.GA); FOS: Physical sciences; QB1-991; T dwarfs; Astrophysics - Astrophysics of Galaxies; Solar and Stellar Astrophysics (astro-ph.SR); L dwarfs

We have used the UKIRT Hemisphere Survey (UHS) combined with UKIDSS Galactic Cluster (GCS), Plane (GPS), and CatWISE2020 catalog to search for new substellar members of nearest open cluster Sun, Hyades. Eight Hyades candidate were identified observed Gemini/GNIRS near-infrared spectrograph. All eight objects are confirmed as brown dwarfs spectral types ranging from L6 T5, two showing signs binarity and/or variability. A kinematic analysis demonstrates that all discoveries likely belong cluster, future radial velocity parallax measurements needed confirm their membership. CWISE J042356.23$+$130414.3, a type would be coldest ($T_{\rm eff}$$\approx$1100 K) lowest-mass ($M$$\approx$30 $M_{\rm Jup}$) free-floating member yet discovered. further find high-probability this work previous studies redder colors than field-age dwarfs, potentially due lower surface gravities super-solar metallicities.