Figure 2

Maximum relative energy errors as functions of \(\pmb{r_{\mathrm{cut}}}\) (left) and \(\pmb{\Delta t_{\mathrm{soft}}/r_{\mathrm{cut}}\sigma}\) (right). Top, middle and bottom panels show the results for \(\theta=0.2,0.4\mbox{ and }0.8\), respectively. For all runs, we use \(\eta=0.1\), \(\Delta t_{\max}=\Delta t_{\mathrm{soft}}/4\) and \(\Delta r_{\mathrm{buff}}=3 \sigma \Delta t_{\mathrm{soft}}\).