Distributions of the fitted properties of N₂H⁺ (1−0) in Serpens South. (a) N₂H⁺ (1−0) excitation temperature, (b) total optical depth, (c) velocity dispersion, and (d) N₂H⁺ column density. The red pixels at the southern boundary of panel a have large uncertainties for the fitted excitation temperatures. The overlaid HCNH⁺ (2−1) integrated-intensity contours are the same as in Fig. 2a.