Fig. 3. Radial velocity as a function of phase from the deepest point in the line profile for the H₂ 1-0 S(1), CO 2-0 high J", and Ti I lines in the 2 µm spectrum of Cyg. The solid curve is representative of the CO v=3 velocity curve (HHS) from the 1.6 µm spectrum. Note the significant departure of the H₂ velocities from the relation established by the other three groups of lines.