Part-sky CMB E-mode power spectrum (binned with Δl = 50 bands) estimated with ABS (green curve). The red curve is the CMB E-mode input power spectrum. The blue curve, which shows the pseudo-power spectrum computed directly from the CMB sky realization without noise/foregrounds, using the Smith and Zaldarriaga E/B separation method, illustrates the uncertainties inherent to the correction of the E–B mixing. The 1-σ statistical errors computed from 50 simulations with independent realizations of the instrumental noise are shown as the light green shadow region. The relative error, , is shown in percentage level (the error in the first bin, which is much larger than the y-axis scale, is not displayed). The symbol colors and sizes illustrate deviations from 0% in respect to the “true” spectrum.