Notes. Listed in the table are all orbital parameters of the object HD 52961. Here, “Period” is the time of one revolution in days; “Eccentricity” defines the elongation of the orbit; T₀ sets the position of the orbit at phase zero; ω is the argument of periapsis, which defines the orientation of the ellipse; K₁ is the highest radial velocity offset from the median; γ is the radial velocity of the mass centre. The semi-major axis and the Roche-lobe radius was calculated assuming an inclination of 60°. The second column shows the best-fit parameters of HD 52961 found using the parametric fit described in Bollen et al. (2022). The tabulated parameters are: (i) inclination angle of the binary system; (θ_out) jet outer angle; (θ_in) jet inner angle; (θ_cav) jet cavity angle; (ϕ_tilt) jet tilt; (v_in) inner jet velocity; (v_out) jet velocity at the jet edges; (c_v) velocity scaling parameter; (p_v) exponent for the velocity profile; (p_ρ, in, p_ρ, out) exponent for the density profile for the outer and inner region; (c_τ) optical depth scaling parameter; (R₁) the radius of the post-AGB star. The term R₂ is the radius of the secondary. Underneath the line, the inner and outer launching radius is shown.