Identifying and characterizing ultracool dwarfs ejected from post-encounter disintegrating systems

Yip, Alexandra K. P.; Kurtev, Radostin; Pinfield, David J.; Marocco, Federico; Gromadzki, Mariusz; Carballo-Bello, Julio A.

Abstract

Disintegrating multiple systems have been previously discovered from kinematic studies of the Hipparcos catalogue. They are presumably the result of dynamical encounters taking place in the Galactic disc between single/multiple systems. In this paper, we aim to expand the search for such systems, to study their properties, as well as to characterize possible low-mass ejecta (i.e. brown dwarfs and planets). We have assembled a list of 15 candidate systems using astrometry from the Tycho-Gaia astrometric solution (later upgraded with Gaia DR3), and here we present the discovery and follow-up of five of them. We have obtained DECam imaging for all five systems and by combining near-infrared photometry and proper motion, we searched for ultracool ejected components. We find that the system consisting of TYC 7731-1951-1, TYC 7731-2128 AB, and TYC 7731-1995-1ABC?, contains one very promising ultracool dwarf candidate. Using additional data from the literature, we have found that three out of five disintegrating system candidates are likely to be true disintegrating systems.

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Título según WOS: ID WOS:000976582600004 Not found in local WOS DB
Título de la Revista: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volumen: 522
Número: 2
Editorial: OXFORD UNIV PRESS
Fecha de publicación: 2023
Página de inicio: 1669
Página final: 1685
DOI:

10.1093/mnras/stad1037

Notas: ISI