Swift/BAT 14–100 keV energy range folded lightcurves of Vela X-1 (blue points), together with the simulated eclipse profiles (dashed lines) using a binary separation α = 1.77 R_∗. Left: the lightcurves corrected for scattering (solid line) were built assuming wind terminal velocity of υ_∞ = 1400 and β = 0.5. Right: same as previously for the remaining models, vXXXXbYY, where XXXX is the wind terminal velocity in km s^-1 and YY is the wind β parameter. The residuals between the model and observations are shown in the bottom panel. The χ² are listed in Table 2.