Scenarios to determine the contribution of the emission component to the spectra. Upper row: case I, only the photospheric Hα spectrum from the primary is absorbed by the jet (denoted by “”). The double-peaked emission component is constant and independent and is thus added (denoted by “+”) to the resulting spectrum. Middle row: case II, the background spectrum is the combined photospheric Hα line plus the emission component. This light is then absorbed by the jet. Lower row: case III, This is the same as case II, except for the fact that the emission component varies as a function of orbital phase. The emission component shown here is taken at phase ϕ = 0.5, and thus weaker than the emission component at phase ϕ = 0 (as can also be seen in Fig. 5).