p-HO 1₁₁–0₀₀ averaged spectra around the (0, 0) position. The average center position is given in ′′ offsets below each spectrum. Top spectra were shifted by 1 K for plotting purposes. Averaged ¹³CO (10–9) spectra (same positions) are overplotted in red. The continuum is removed for both lines, horizontal gray lines mark the zero levels, and the vertical gray lines mark 100 km s^-1.