The <i>Gaia</i> ultracool dwarf sample – VI. Spectral types and properties of 51 ultracool dwarfs
ABSTRACT Near-infrared spectra from the IRTF/SpeX and Blanco/ARCoIRIS telescope/instrument combinations are used for spectroscopic classification, to measure radial velocities, and for the inference of astrophysical properties of 51 Gaia-selected nearby ultracool dwarfs. In this sample, 44 are newly classified in the near infrared. All but one of the UCDs are within 100 pc, and 37 lie within 50 pc. We find a total of 26 M-types, 24 L-types, and one T-type in our sample. The positions of the majority of the UCDs on colour–magnitude diagrams and with evolutionary cooling track plots indicate that they are largely old and stellar in nature. There are a few UCDs of particular interest which lie away from expected trends, highlighting potential young, binary, and thick disc/subdwarf UCDs. From spectral and kinematic analyses, we identify UCDs of particular interest for further investigation, including seven potentially young UCDs, three thick disc UCDs, one subdwarf, six wide binaries, and six unresolved binaries.
Authors
- J. C. Beamín (ORCID: https://orcid.org/0000-0002-8409-6534)
- Adam J. Burgasser (ORCID: https://orcid.org/0000-0002-6523-9536)
- D. J. Pinfield (ORCID: https://orcid.org/0000-0002-7804-4260)
- R. L. Smart (ORCID: https://orcid.org/0000-0002-4424-4766)
- Federico Marocco (ORCID: https://orcid.org/0000-0001-7519-1700)
- Jonathan Gagné (ORCID: https://orcid.org/0000-0002-2592-9612)
- H. R. A. Jones (ORCID: https://orcid.org/0000-0003-0433-3665)
- William Cooper (ORCID: https://orcid.org/0000-0003-3501-8967)
- Leslie Moranta (ORCID: https://orcid.org/0000-0001-7171-5538)
- Gemma Cheng (ORCID: https://orcid.org/0009-0003-5234-0437)
Institutions
- California Institute of Technology (US)
- American Museum of Natural History (US)
- University of Hertfordshire (GB)
- Fundación Chile (CL)
- Espace pour la vie (CA)
- University of California San Diego (US)
- Rio Tinto (Canada) (CA)
- Osservatorio Astrofisico di Torino (IT)
- Infrared Processing and Analysis Center (US)
- Université de Montréal (CA)
- National Institute for Astrophysics (IT)
Publication Details
- Journal
- Monthly Notices of the Royal Astronomical Society
- Published
- 2025-03-17
- DOI
- https://doi.org/10.1093/mnras/staf432
- Citations
- 2
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 2.31