Dynamical analysis of the orbital parameters of the HD 82943 planetary system

We present a preliminary analysis of the dynamical stability of the HD 82943 planetary system. It contains two Jovian planets orbiting the parent star with the orbital periods commensurability close to 2 : 1. The announced initial condition, derived for this system by a two-planetary Keplerian fit, leads to a self-destructing system. We analyze a neighborhood of this initial condition in the orbital parameters' space, using the MEGNO (Mean Exponential Growth of Nearby Orbits) indicator, and we find the stability zones of the system. We determine an initial condition heuristically, providing a stable system that well reconstructs the observed radial velocity curve. Using a synthetic radial velocity curve that mimics the distribution of the observational data, we obtain other probable and stable initial conditions by the N-body fit procedure. Our study demonstrates that analysis of the global dynamics is useful in the process of fitting the initial conditions to the observational data.