Overlay of the ¹³CO (2–1) mean absorption (dashed contours) on the 1.4 mm continuum emission (grayscale). The absorption has been averaged over the velocity interval 98.9–105.9 km s^-1. Negative contours are –0.06 and −0.12 Jy beam^-1, while positive contours range from 0.08 to 0.56 in steps of 0.08 Jy beam^-1 (1σ ≃ 0.02 Jy beam^-1). Grayscale contours for the continuum emission are the same as in Fig. 1. The synthesized beam is shown in the lower righthand corner.