Integrated intensity maps at 6″ resolution of NGC 3351, NGC 3627, and NGC 4321 from left to right. Top and middle rows: HCN(3–2) and HCO⁺(3–2) maps. The white contours correspond to S/N  =  5 and the grey circles represent the 6″ beam. Offsets are relative to the positions in Table 1. Bottom row: PHANGS-ALMA CO(2–1) maps. Black contours correspond to 10, 30, 50, and 70% of the maximum in each CO(2–1) image at the native ∼1.5″ resolution. The white circles indicate the fields of the HCN(3–2) and HCO⁺(3–2) observations with the ACA.