Gaia0007-1605: an old triple system with an inner brown dwarf-white dwarf binary and an outer white dwarf companion
Alberto Rebassa-Mansergas, Siyi Xu, Roberto Raddi, Anna F. Pala,, Enrique Solano, Santiago Torres, Francisco Jim\'enez-Esteban, Patricia, Cruz

TL;DR
This paper reports the discovery and analysis of Gaia0007-1605, a hierarchical triple system with an inner brown dwarf-white dwarf binary and an outer white dwarf, providing insights into its formation, evolution, and age.
Contribution
It presents the first detailed characterization of an inner brown dwarf-white dwarf binary within a triple system, including spectroscopic measurements and orbital analysis.
Findings
Inner binary consists of a brown dwarf and a white dwarf with a 1.045-day orbit.
System is approximately 10 billion years old based on kinematic analysis.
Detected irradiation-induced variability in the brown dwarf from TESS light curves.
Abstract
We identify Gaia0007-1605AC as the first inner brown dwarf-white dwarf binary of a hierarchical triple system in which the outer component is another white dwarf (Gaia0007-1605B). From optical/near-infrared spectroscopy obtained at the Very Large Telescope with the X-Shooter instrument and/or from Gaia photometry plus SED fitting, we determine the effective temperatures and masses of the two white dwarfs (12018+-68 K, 0.54+-0.01 Msun for Gaia0007-1605A and 4445+-116 K, 0.56+-0.05 Msun for Gaia0007-1605B) and the effective temperature of the brown dwarf (1850+-50 K; corresponding to a spectral type L3+-1). By analysing the available TESS light curves of Gaia0007-1605AC we detect a signal at 1.0446+-0.0015 days with an amplitude of 6.25 ppt, which we interpret as the orbital period modulated from irradiation effects of the white dwarf on the brown dwarf's surface. This drives us to…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsStellar, planetary, and galactic studies · Astronomy and Astrophysical Research · Astrophysical Phenomena and Observations
