Convergence of the emerging linear polarization Q/I: evolution of the step increment Δ(Q/I) as a function of the step number N. The aim is to show that the step increment decreases more rapidly than the inverse of the step number 1/N (as for a Riemann series). In this respect, their ratio is the upper plot and the logarithm of their ratio is the lower plot, which also includes linear fits and their equations.