We investigate the BPS configuration of the multi D-vortices produced from the D2${bar {rm D}}$2 system. Based on the DBI-type action with a Gaussian-type runaway potential for a complex tachyon field, the BPS limit is achieved when the tachyon profile is thin. The solution states randomly-distributed $n$ static D-vortices with zero interaction. With the obtained BPS configuration, we derive the relativistic Lagrangian which describes the dynamics of free massive D-vortices. We also discuss the 90${}^{circ}$ and 180${}^{circ}$ scattering of two identical D-vortices, and present its implications on the reconnection in the dynamics of cosmic superstrings.
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