Integrated-intensity maps of H¹³CO⁺ (top panels), CCH (middle), and c-C₃H₂ (bottom) in color scale and colored contours. The left panels correspond to redshifted velocities from the systemic velocity, v_sys ~ 3.6 km s⁻¹, and the right panels show blueshifted velocities. The ranges are specified in the text insets of each panel. Overlaid on all panels, we plot the 1.3 mm ALMA continuum (white contours) and the CO (3–2) integrated emission (black contours) from −2.0 to 9.2 km s⁻¹. The H¹³CO⁺ and CCH contours are [−5,10,15,20] times the 1σ rms noise level, which is 1.0 mJy beam⁻¹ km s⁻¹ for both maps of H¹³CO⁺, and 1.1 mJy beam⁻¹ km s⁻¹ for both CCH maps. The c-C₃H₂ contours are [−5,3,5,7,10] times the 1σ rms noise level, which is 1.8 mJy beam⁻¹ km s⁻¹ for both maps. Negative contours are represented with dashed lines. CO (3–2) contours are [50,100,200] times the 1σ rms noise of 1.2 mJy beam⁻¹ km s⁻¹. The rms noise of the integrated-intensity maps has been measured before correcting for the primary beam response. The 1.3 mm continuum contours are [20,30,40,50,100, and 200] times the 1σ rms noise of 0.14 mJy beam⁻¹. The dashed curve and arrows in the redshifted panels indicate the transition region between the elongated structure (east, outside the dashed curve) and the rotating envelope (west, delineated by the dashed curve). The red and blue polygons cover the area used to obtain the PV diagrams shown in Figure 3. The synthesized beam sizes are 0.34″ × 0.33″ for the continuum emission, 0.13″ × 0.10″ for CO (3–2), 0.46″ × 0.39″ for H¹³CO⁺ and CCH, and 0.42″ × 0.39″ for c-C₃H₂. The beam ellipses for the H¹³CO⁺, CCH and c-C₃H₂ maps are plotted in the bottom left corner of the corresponding panels. The center of the images is at α(2000)=17h11m23.125s, δ(2000)=−27°24′32.87″.