Spectra extracted from the atomic jet knot and the H₂ features labelled A1 & A2. Top: Integrated spectrum extracted using a circular aperture of radius $0\stackrel{″}{.}4$ from atomic jet knot located at 1″ offset from source position. Centre: Integrated spectrum extracted using a circular aperture of radius $0\stackrel{″}{.}4$ from base of left cavity wall traced in H₂, position A1. Bottom: Integrated spectrum extracted using a circular aperture of radius $0\stackrel{″}{.}4$ from base of cavity wall, position A2.