Investigating Possible Binarity for GJ 229B

Autor: Howe, Alex R., Mandell, Avi M., McElwain, Michael W.
Rok vydání: 2023
Předmět:
Druh dokumentu: Working Paper
DOI: 10.3847/2041-8213/acdd76
Popis: GJ 229B, the first type-T brown dwarf to be discovered, has presented a tension between comparisons with evolutionary models and the larger-than-expected mass and radius values derived from spectroscopic and astrometric observations. We examine the hypothesis that GJ 229B is actually a binary sub-stellar object by using two grid-based fits using evolutionary models to explore the range of mass ratios of the possible binary components. We find that the best-fit component values are most consistent with a roughly 2:1 binary mass ratio and an age range of 2-6 Gyr. The observed temperatures, masses, and apparent radii match expected values from evolutionary models for a binary much better than a single-object model, but more detailed observations and modeling are needed to definitively confirm the binary hypothesis.
Comment: 9 pages, 3 figures, 2 tables, accepted for publication in ApJL
Databáze: arXiv