RMS-weighted stacked spectra for region A and region B are shown in the left panel. Region A represents areas where HCN(1–0) is detected but HCN(4–3) is not, while region B corresponds to areas where HCO⁺(1–0) is detected but HCO⁺(4–3) is not. To minimize interference from high-noise spectra, data points at offsets along the minor axis of ±40 have been excluded. The specific locations of regions A and B are shown in the right panel.