DSS-43 observations of HOPS-108. Panels a–c: ammonia inversion lines. Green curves correspond to HFS fits to the (1,1) and (2,2) transitions and a two-component Gaussian fit to the (3,3) transition. Panel d: normalized χ² of the Weeds fit as a function of the excitation temperature. Panel e: best Weeds fit to the (1,1) transition corresponding to an excitation temperature of 8 K. Panels f–m : spectra of other transitions included in the analysis. Green lines correspond to a single-component Gaussian fit and 3σ upper limits to CCS, C₃S, and c-C₃HD.