Gaussian optical depth fits to the observed ground-state NH₃ absorptions, corresponding to components in formaldehyde. The spectrum in black is the continuum-subtracted (T_C = 1.29 K) observed spectrum. The velocity ranges over which the fits are made are highlighted in green and the fits themselves are shown in red. The blue dashed boxes mark the velocity ranges over which the absorption is integrated for the column density comparisons in Fig. 3.