Position-velocity diagrams of CO(5–4) in BR1202–0725. Left: Dec-velocity cut through the SE source. The main line has two peaks, at −70 and + 110 km s^-1, separated by + 0.4″ in dec. At negative velocities, a narrow-line CO tail extends >3″ southwest. This tail to the SW is near, but does not coincide with, the weak SW continuum source found by Wagg et al. (2012). Right: RA-velocity cuts through the NW source. Note the large linewidth, which includes the strong line core near −200 km s^-1, and the weaker plateau, that may be another merger galaxy, at +400 km s^-1, and 0.6″ to the west or northwest. For both diagrams, velocity offsets are relative to 101.190 GHz (z = 4.6949), and contours start at 2σ and increase in steps of 1-σ (0.37 mJy/beam). The beam is 1.6″ × 0.7″ (PA 15°); position offsets are relative to the map phase center at RA 12:05:23.11, Dec –07:42:32.10 (J2000).