Maps of the integrated emission over the hydrogen recombination lines indicated in the top right corner of each panel. The emission from the HMC is not plotted because the recombination lines are heavily blended with stronger molecular transitions. The circle in the bottomright corner is the synthesised beam. The offsets are relative to the phase centre of the ALMA observations. The emission of the H54γ line is contaminated by two hyperfine components of the NS J = 5/2 → 3/2 transition.