Right: edge-on coplanar grid with jitter included. The eccentricities of both planets are varied in the range from 0.001 to 0.251 with steps of 0.005, while the other orbital parameters and the zero-point offset were fitted until the minimum is achieved. The solid black contours indicate the stable fits, while the dashed contours indicate fits where the system survives the dynamical tests, but with chaotic scattering behavior. While the best dynamical fit is unstable (white star), we found two stability islands where long-term (10⁸ yr) stability is achieved. With a moderate e_b, at the 1σ border (blue contours), a stable 2:1 MMR region exists, and at lower eccentricities a broad stability region can be seen at more than 3σ from the best fit, without showing any signs of a low-order MMR. Left: higher resolution zoom of the stable 2:1 resonant region.