 ![Distribution of cluster particles and disk particles around clusters in $x$-$y$ plane (left) and $v_{R}$-$v_{\phi}$ phase (right). The cluster shown in the top panels is the same one shown in Figure \[fig:cluster00\] at a time of 0.00 Gyr, when the cluster is located at its perigalacticon. The bottom panels show a cluster, which is moving from its perigalacticon to apogalacticon at a time of 0 Gyr. Crosses and points indicate cluster and disk particles, respectively. In the left panels, colors indicate the velocity shown in right panels. Black dotted and dashed curves show orbits obtained from the simulation and circular orbits at the distance of the cluster from the galactic center, respectively. Yellow circles show the 0 and 0 kpc radius from the center-of-mass position of the cluster. In the right panels, blue, red, green, and black crosses indicate cluster particles with $<$0, 0-0, 0-0, and $>$0 $\rm km~s^{-0}$ from the mean velocity of the cluster particles. Cyan points indicate disk particles which are located within 0 kpc from the cluster center. Disk particles which are located within 0 kpc and have velocities $<$0 and 0-0 $\rm km~s^{-0}$ from the mean velocity of the cluster are shown in the left panels as blue and red points, respectively.\[fig:xyv\]](xyv_cl00