X/CS(1–0) intensity ratios in the same selected velocity ranges as Fig. 2. X stands for SiO(2–1), H¹³CO⁺(1–0), HN¹³C(1–0), HNCO(5–4), and C¹⁸O(1–0). Molecular emission is shown in contour levels, which are −3σ (dashed contour), 3σ, from 2.0 to 8 in steps of 1.5 K km s^-1. The 3σ level of each molecule is the same as in Fig. 2. Intensity ratio maps take upper and lower limits into account, using the 3σ value of each map as the limit value. The wedges to the left show the color scale of the different intensity ratios. Row at the bottom shows CS(1–0) maps of Tsuboi et al. (1999) to compare and show which pixels present meaningful ratios or are only limits (their contour levels and intensity scale are the same as in Fig. 2).