Representation of the KS diagram across the merger sequence based on beam-sized region identification. From left to right and top to bottom, the merger stages are isolated galaxies (blue), galaxy pairs (red), early-stage mergers (orange), mid-stage mergers (magenta), and late-stage mergers (black). The black solid line represents the best fit for each dataset. The Spearman’s rank correlation coefficients (ρ_s) and the power-law indices (N) of the derived best-fit KS relations are indicated. The bottom right panel shows the mean values of log₁₀Σ_SFR and log₁₀Σ_H2; the error bars represent the mean absolute deviation for each merger stage. The grey dashed lines mark constant star formation efficiencies (SFE = Σ_SFR/Σ_H2).