Flux and polarization spectra for different mean electron drift velocities in the full model. The parameters are as follows: B_p = 5 × 10¹³ G, R = 10 km, kT_e = 10 keV, kT_s = 0.6 keV, θ = 35°, ξ_τ = 0.5, and a hot spot at (θ_s, ϕ_s) = (53°, 37°). Results are shown for β₀ = 0.2, 0.5, and 0.8, and are compared with the unscattered case.