Left: Column density map of CH₃CCH derived with the (5₁−4₁) transition. The solid contour indicates the 3σ level of the column density. The markers represent the dust peak (triangle) and the molecular emission peaks of CH₃OH (diamond), CH₃CCH (star), and c-C₃H₂ (plus sign). Right: Corresponding deuteration maps. Only pixels above the 3σ level of the respective integrated intensities are plotted.