Spectra extracted from a 0″.6 ellipse. (A) Individual transitions. (B) Spectra of the two stacked SO lines, and the same spectra mirrored. (C) Spectra of the two stacked SO lines with continuum subtraction and without continuum subtraction in the UV domain (after subtracting the average value of the line-free continuum emission channels). (D) Spectra of the two stacked SO lines from the ALMA Cycle 0 observations presented in Booth et al. (2018) and the Cycle 7 observations presented in this work. The Cycle 7 data have been imaged at 1.0 km s⁻¹ in order to make a direct comparison to the Cycle 0 data. The noise calculated from the line-free channels in each respective spectrum is shown by a bar in the top left corner of the plot.