Example of a simulation of the dynamics of the β Pic planetary system with three planets, β Pic b (red), β Pic c (blue) and an additional planet β Pic d (green), and the disk of planetesimals (black). The initial orbital parameters of β Pic b and c are taken from Table 1. In this example, the initial orbital parameters of β Pic d are: m_d = 0.05 M_Jup, a_d = 40 au, and e_d = 0.05. The plotting conventions are identical to Fig. 1. This combination still generates a disk inner edge at 50 au, but there is now enough space between β Pic b and β Pic d to allow an additional ring of particles to exist at ~30 au.