Example of an instantaneous polar profile of an azimuthal average of b ²/ρ, as evaluated at the BH event horizon, for ﹩{\sigma }_{\ \max }=50﹩. At θ/π = 0.5 we see the density-dominated disk, whereas in the polar regions, ∣θ∣/π ≳ 0.1, we notice the contamination due to density floors. Due to the steepness of the profile a σ cut, σ < 30, allows to select most of the disk while removing the floor contamination in highly magnetized polar regions.