Spectra of HCO⁺, HNC, N₂H⁺, and C¹⁸O extracted from each core in Fig. 1. These spectra are the average within one beam size (~27″). The green curves on N₂H⁺ are from the HFS fit, and on other spectra are from the Gaussian fit by masking the absorption dip with GILDAS/CLASS software. To better show the HFS fit, the strongest HFS line was set the systemic velocity component (continuation in Fig. A.2).