Fig. 4.

Spectra of detected molecules over ten points around the AB Aur disk. In color gradient, the C¹⁸O J=2→1 integrated intensity map from Fig. 1. Contour levels are from 40% to 90% in steps of 10% the maximum (15 K × km s⁻¹). The position of the central source is marked by a red star. The arrow indicates the direction of the ionized jet (Rodríguez et al. 2014). The ten boxes labeled from A to K show the spectra of the ¹³CO J=2→1, C¹⁸O J=2→1, SO J=5₆→4₅, and H₂CO J=3_0,3→2_0,2 lines toward selected positions. We note that the SO emission is extremely weak (even undetected) toward the southwest.