Radial velocities of the s-wave (red and orange diamonds for night 1 and night 2, respectively) and of the fuzzball-wave (blue and green squares for night 1 and night 2, respectively). The red sine curve and horizontal lines are the night 1 best fit radial and γ velocity for the s-wave, respectively (see Sect. 3.2.1 for details). The blue sine curve and horizontal line are the night 1 best fit radial and γ velocity, respectively, for the fuzzball emission (see Sect. 3.2.2 for details). The two vertical bars on the bottom right corner of the panel represent the radial velocity measurement 1σ uncertainties: 30 km s⁻¹ in purple for the UVB arm measurements and 20 km s⁻¹ in dark green for the VIS arm measurements.