H29α and CH₃ CCH Gaussian fits to the emission from G336.98. The blue curve shows the overall emission spectrum, the orange curve shows the Gaussian fit to H29α, and the other colour curves show the Gaussian fits to the CH₃CCH components. In the top panel, the blue curve shows the original spectrum; the grey fill indicates the sum of the Gaussian components at each velocity. In the middle panel, the molecular Gaussian components have been removed, and in the bottom panel, the H29α has been removed, showing how well the individual Gaussian components fit the spectrum. The additional, unfit lines correspond to other species such as methanol and ethanol (at ~–130 and ~–80 km s⁻¹ , respectively), which were not included in the XCLASS fit.