From left to right, top to bottom: integrated intensity map of HCO⁺(1−0), CS(2−1), CN(1−0), HCN(1−0), HNC(1−0), N₂H⁺, CCH, and H¹³CO⁺ (1−0). The white ellipses mark the approximate inner and outer edges of the dust ring at 180 au and 260 au, respectively. The beam size is indicated in the lower left corner and the colour scale is on the right is units of Jy beam⁻¹ km s⁻¹. The intensity was integrated in the velocity range from 4.0 to 9.0 km s⁻¹ with the threshold of 3σ. Contour levels are spaced by 5σ in the maps of HCO⁺ and CS(2−1), and 3σ in the maps of CN, HCN, HNC, N₂H⁺, CCH, and H¹³CO⁺ (1−0).