Central position of the clumps found in ¹²CO, ¹³CO, CS, HCO⁺, and HCN, plotted over contours of the peak main beam temperature of ¹²CO. The contours correspond to 5, 10, 100, and 200 times the rms of the ¹²CO line emission (47 mK). The blue crosses mark the central position of the clumps found in the ¹²CO in Sect. 3.1. The yellow arrowheads point toward the central positions of the ¹³CO clumps. The green arrowheads point toward the central positions of the CS clumps. The red arrowheads point toward the central positions of the HCO⁺ clumps. The purple arrowheads point toward the central positions of the HCN clumps. The red ellipse in the lower right corner represents the beam size.