Orbital projection in the Galactic plane (top left) and in the two vertical planes (bottom left and top right) of our bona fide sample of 26 members of β Pic, integrated back in time 50 Myr, under the new A&S potential. The orbits are colour-coded with the backwards time, the black squares represent the positions in the present (t = 0 Myr), and the blue dots represent positions at birth time (t = −18.5 Myr). The filled markers correspond to the core of β Pic defined in Sect. 3.2.