Velocity variations along the spines of F1 and F2, along with the changes in the hydrogen column density, self-gravitational potential Φ_self, and mutual gravitational potential Φ_mutual. In the hydrogen column density panel, the positions and numbers of the corresponding clumps along the spines are labeled. The red labels indicate clumps that are in a state of virial collapse. The clump identification and detailed physical parameters are described in Sect. 3.6 and listed in Table 2.