The effect of the giant planets on the dynamical evolution of the mutual orbits of trans-Neptunian binaries

BRUNINI ADRIÁN

Monthly Notices of the Royal Astronomical Society

Oxford University Press

Lugar: Londres; Año: 2023 vol. 522 p. 3067 - 3075

The action of tidal friction, coupled with the Kozai cycles, dras-tically changed the original orbits of trans-Neptunian binaries (TNBs). Thedynamics of the Kozai mechanism is driven by the solar torque on the mu-tual orbit, so that the orientation of the latter relative to the heliocentricorbital plane plays a fundamental role in this process, both in the magnitudeand in the characteristic of the cycles. In this way, any eect that makes thisrelative orientation vary may be relevant in the dynamics of the process.In this paper, we will focus on the eect that the perturbations of the gi-ant planets on the heliocentric orbit of TNBs have on the dynamics of theKozai cycles and tidal friction. For this task, we have performed numericalsimulations of the evolution of a synthetic population of TNBs subject toKozai cycles and tidal friction, and adding planetary perturbation on theirheliocentric orbits. We found that in a non-negligible fraction of cases ( 25%), this additional perturbation produces substantial changes in the orbitalevolution. The slow precession of the heliocentric orbit and the variation ofits inclination can make the dynamical evolution of the mutual orbits veryirregular, completely changing the morphology of the Kozai cycles. Whenthese variations are coupled to tidal friction, the life-time of the TNBs canchange substantially.