Testing a hypothesis of the \nu Octantis planetary system

TL;DR

This study explores the orbital stability of a potential Jovian planet in the e9 Octantis system, finding stable retrograde solutions within tiny phase space regions, but questioning the planet's formation due to dynamical perturbations.

Contribution

It provides the first self-consistent Newtonian analysis of the system, identifying stable retrograde orbits and introducing a new MPI-based computational framework for large-scale simulations.

Findings

Stable retrograde orbit solutions found within tiny phase space regions.

The stable regions are structured by overlapping mean motion resonances.

The existence of a real planet remains uncertain due to formation challenges.

Abstract

We investigate the orbital stability of a putative Jovian planet in a compact binary \nu Octantis reported by Ramm et al. We re-analyzed published radial velocity data in terms of self-consistent Newtonian model and we found stable best-fit solutions that obey observational constraints. They correspond to retrograde orbits, in accord with an earlier hypothesis of Eberle & Cuntz, with apsidal lines anti-aligned with the apses of the binary. The best-fit solutions are confined to tiny stable regions of the phase space. These regions have a structure of the Arnold web formed by overlapping low-order mean motion resonances and their sub-resonances. The presence of a real planet is still questionable, because its formation would be hindered by strong dynamical perturbations. Our numerical study makes use of a new computational Message Passing Interface (MPI) framework MECHANIC developed to run massive numerical experiments on CPU clusters.