Maps of the line and continuum emission toward the G31.41 HMC. The line maps have been obtained by averaging the emission under the whole line profile, namely from 88.9 km s^-1 to 103.9 km s^-1 (see Fig. 1, bottom). The tracer used is indicated in the top right of each panel. The two white points mark the positions of the free-free-continuum sources detected by Cesaroni et al. (2010). The contour levels start from 0.072 Jy/beam and increase in steps of 0.12 Jy/beam for all line maps, and range from 0.035 Jy/beam to 1.785 Jy/beam in steps of 0.175 Jy/beam for the continuum map. Offsets are measured with respect to the phase center α(J2000) = 18^h47^m34315 δ(J2000) = –01°12′459. The ellipse in the bottom right denotes the FWHP of the synthesized beam.