High angular resolution maps of the integrated intensity of H¹³CO⁺, HCO, C₂H, and c-C₃H₂, and the 7.7   μm PAH emission. Maps are rotated by 14° counter-clockwise around the projection center, located at (δx,δy) = (20′′,0′′), to bring the illuminated star direction in the horizontal direction. The horizontal zero is set at the PDR edge. The emission of all lines is integrated between 10.1 and 11.1   km   s^-1. Displayed integrated intensities are expressed in the main beam temperature scale. Contour levels are shown in the grey-scale lookup tables. The red vertical line shows the PDR edge and the blue and green crosses show the dense core and PDR positions, respectively.