SPH and sink particle plots of Boss-Bodenheimer test at times a) t = 0.025   Myr, b) t = 0.033   Myr and c) t = 0.055   Myr. SPH particles are represented by black dots (only one in every three plotted for clarity) and the position and motion of the sink particles are represented by the red lines. The first tile (t = 0.025   Myr) shows the particle distribution just after the formation of the two sinks in the condensations that form either end of the bar. The subsequent times shows the motion of the sink particles as they move with the gas and the small disks that form around each sink. All figures show the region  −0.005 < x < 0.005,  −0.005 < y < 0.005.