Ultracool dwarfs in Gaia DR3

Abstract

Aims. In this work we use the Gaia DR3 set of ultracool dwarf candidates and complement the Gaia spectrophotometry with additional photometry in order to characterise its global properties. This includes the inference of the distances, their locus in the Gaia colour-absolute magnitude diagram and the (biased through selection) luminosity function in the faint end of the Main Sequence. We study the overall changes in the Gaia RP spectra as a function of spectral type. We study the UCDs in binary systems, attempt to identify low-mass members of nearby young associations, star forming regions and clusters, and analyse their variability properties. Results. We detect 57 young, kinematically homogeneous groups some of which are identified as well known star forming regions, associations and clusters of different ages. We find that the primary members of 880 binary systems with a UCD belong mainly to the thin and thick disk components of the Milky Way. We identify 1109 variable UCDs using the variability tables in the Gaia archive, 728 of which belong to the star forming regions defined by HMAC. We define two groups of variable UCDs with extreme bright or faint outliers. Conclusions. The set of sources identified as UCDs in the Gaia archive contains a wealth of information that will require focused follow-up studies and observations. It will help to advance our understanding of the nature of the faint end of the Main Sequence and the stellar/substellar transition.

Accepted by Astronomy and Astrophysics. 29 pages, 20 figures plus 3 appendices

References in corpus (32)

• The Gaia mission
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• galpy: A Python Library for Galactic Dynamics
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Analytical theory for the initial mass function: CO clumps and prestellar cores
• The 0.8-14.5 micron Spectra of Mid-L to Mid-T Dwarfs: Diagnostics of Effective Temperature, Grain Sedimentation, Gas Transport, and Surface Gravity
• Meeting the Cool Neighbors. IX. The Luminosity Function of M7-L8 Ultracool Dwarfs in the Field
• The mass distribution in the Galactic Centre from interferometric astrometry of multiple stellar orbits
• The Hawaii Infrared Parallax Program. II. Young Ultracool Field Dwarfs
• Methane, Carbon Monoxide, and Ammonia in Brown Dwarfs and Self-Luminous Giant Planets
• Gaia Data Release 3: Astrophysical parameters inference system (Apsis) I -- methods and content overview
• Gaia Data Release 3: Processing and validation of BP/RP low-resolution spectral data
• Activity and Kinematics of Ultracool Dwarfs Including An Amazing Flare Observation
• Gaia Data Release 3: External calibration of BP/RP low-resolution spectroscopic data
• The Field Substellar Mass Function Based on the Full-sky 20-pc Census of 525 L, T, and Y Dwarfs
• Gravitational fragmentation and the formation of brown dwarfs in stellar clusters
• Discovery of Two Nearby, Peculiar L Dwarfs from the 2MASS Proper Motion Survey: Young or Metal-Rich?
• Gaia Data Release 3: Apsis II -- Stellar Parameters
• The minimum mass for star formation, and the origin of binary brown dwarfs
• A search for binary systems among the nearest L dwarfs
• SpeX Spectroscopy of Unresolved Very Low Mass Binaries. II. Identification of Fourteen Candidate Binaries with Late-M/Early-L and T Dwarf Components
• Exploring the substellar temperature regime down to ~550K
• Internal calibration of Gaia BP/RP low-resolution spectra
• Stars with Photometrically Young Gaia Luminosities Around the Solar System (SPYGLASS) I: Mapping Young Stellar Structures and their Star Formation Histories
• CSI 2264: Characterizing Young Stars in NGC 2264 with Short-Duration, Periodic Flux Dips in their Light Curves
• Gaia DR3: Apsis III -- Non-stellar content and source classification
• The Brown dwarf Atmosphere Monitoring (BAM) Project I: The largest near-IR monitoring survey of L- & T-dwarfs
• New, nearby bright southern ultracool dwarfs
• Southern Infrared Proper Motion Survey II: A sample of low mass stars with μ> 0.1''/yr
• Gaia Data Release 3: A Golden Sample of Astrophysical Parameters
• Selection Functions in Astronomical Data Modeling, with the Space Density of White Dwarfs as Worked Example
• A high resolution spectral atlas of brown dwarfs

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• Near-infrared spectroscopic characterisation of Gaia ultra-cool dwarf candidates; Spectral types and peculiarities
• The Gaia Ultracool Dwarf Sample -- IV. GTC/OSIRIS optical spectra of Gaia late-M and L dwarfs
• Gaia's faintest stars