Continuum-subtracted spectra of HF J = 1–0 and H₂O (2₂₀–2₁₁) in BR 1202-0725. The black line are the data after being Hanning smoothed to a velocity resolution of 11 km s⁻¹. The red line shows the data binned into six channels and subsequently Hanning smoothed to a velocity resolution of 66 km s⁻¹. Top: spectrum of H₂O emission from the SMG. Indicated with the magenta dashed line is the velocity of the expected HF J = 1–0 feature, which may (at best) be tentatively detected, relative to the velocity of H₂O. Bottom: spectrum of HF J = 1–0 and H₂O (2₂₀–2₁₁) emission from the QSO. The zero-velocity of the QSO is derived from a Gaussian fit to the H₂O profile of the QSO, resulting in z = 4.6948 ± 0.0001. The redshift of the SMG is assumed to be z = 4.6915 from Carilli et al. (2013). The Gaussian functions represented with a solid line are fits to the HF (magenta) and H₂O (blue) emission, as summarized in Table 1. The Gaussian represented with the dotted brown line for the SMG is the fit to the [CII] line (Carilli et al. 2013). The horizontal axis on the bottom (top) gives the corresponding velocity centered on the HF (H₂O) line, as indicated with the magenta (blue) dashed line. The light gray region indicates the gap in the spectra between the two spectral windows.