N₂H⁺(1 − 0) moment maps of the PdBI-only data toward IRDC 18310-4. The left, middle and right panel show in color the 0th moment (integrated intensity), 1st moment (intensity-weighted peak velocity) and 2nd moment (intensity-weighted linewidth), respectively. The moments were again extracted for the isolated hyperfine component − 8.0 km s^-1 from the line center. The 1st moment was calculated from this isolated hyperfine component and then shifted toward by + 8.0 km s^-1 to the v_lsr of the source again. The white contours outline the 70 μm extinction feature and the stars mark the 3.2 mm peak positions from Fig. 2. The synthesized beam and a scale-bar are shown again.