Identify the dynamically viable orbital-orientation family for the circumtriple disk

Determine which of the aligned and strongly misaligned orbital-orientation families permitted by the astrometric constraints can simultaneously reproduce the inferred hierarchical-triple architecture and the observed properties of the GG Tau A circumtriple disk.

Background

The joint orbital fit leaves two principal orientation families relative to the circumtriple ring: a relatively aligned family near 13 degrees and a strongly misaligned family near 73 degrees. The inner and outer stellar orbits likewise retain moderate- and high-mutual-inclination solutions.

These alternatives have different secular dynamical consequences, including possible inclination–eccentricity exchange and different effects on the disk cavity and morphology. The paper therefore identifies dedicated dynamical modeling as necessary to determine which family is physically compatible with both the stellar architecture and the disk observations.

References

A dedicated dynamical study will therefore be required to determine which of these orientation families can simultaneously reproduce the orbital architecture inferred here and the observed properties of the disk.

— A self-consistent orbital architecture for GG Tau A. I. Simultaneous orbital fitting of the hierarchical triple  (2609.17322 - Lacquement et al., 15 Sep 2026) in Section 5.1, Discussion, subsection “Dynamical implications”