PAH band ratio diagrams for ﹩0\mathop{.}\limits^{^{\prime\prime} }2\times 0\mathop{.}\limits^{^{\prime\prime} }2﹩ spaxels in the central ∼4″ × 4″ regions of the five AGN targets, color-coded by the strength indicators of (a) shock processing (rH₂) and (b) AGN irradiation (rNe). The horizontal dashed lines mark the empirical demarcation at PAH 11.3/7.7 = 0.3. The reddish and bluish crosses in panels (a) and (b) show, for the five AGN targets, the median PAH band ratios of the spaxels in bins of increasing log (rH₂) of [−2, −1.5], [−1.5, −1.0], [−1.0, −0.5], and [−0.5, 0], and increasing log (rNe) of [−2, −1.5], [−1.5, −0.75], [−0.75, 0], and [0, 0.5] (from light to dark), respectively. The gray star labeled “SFG” represents the median PAH band ratios of the spatially resolved spaxels in star-forming galaxies measured by L. Zhang et al. (2022); the individual star formation spaxels, which are clustered around the median value, are omitted for clarity. The grids marked by a plus sign in each panel show model predictions of PAH band ratios from D. Rigopoulou et al. (2024) for neutral (top grids), 70% ionized (middle grids), and fully ionized (bottom grids) PAHs of various sizes (carbon number N_C = 20–400, increasing from the right to the left boundary of each grid). The grids span the interstellar radiation field (ISRF; top boundary) up to 10³ × ISRF (bottom boundary).