NILC residuals for SWIPE+Planck dataset with the d1s1 Galactic model. On the left: Mean angular power spectra of NILC foregrounds (solid) and noise (dashed) residuals over 200 simulations. On the right: Posterior distributions of an effective tensor-to-scalar ratio fitted to the foregrounds residuals in the case of half de-lensing (A_L = 0.5). For the estimation of the posteriors, a binning scheme of Δℓ = 15 has been used to make the angular power spectrum Gaussianly distributed (see Sect. 4.2). On the top: Blue and red lines represent the results when E–B leakage is corrected with, respectively, the iterative and inpainting recycling methods (rit-NILC and rin-NILC). On the bottom: Results when the ZB- (blue) and hybrid ZB-NILC (red) methods are applied. The adopted binning scheme is Δℓ = 6 for 5 ≤ ℓ ≤ 28 and Δℓ = 15 for ℓ ≥ 29 on the top left, while Δℓ = 6 for 2 ≤ ℓ ≤ 19 and Δℓ = 15 for ℓ ≥ 20 on the bottom left. In both cases the chosen binning strategy is just for visualisation purposes. Everywhere the grey region represents the primordial tensor BB angular power spectrum for r ∈ [0.015, 0.03]. The lower bound represents the targeted upper limit at 95% CL by LSPE in case of no detection, the upper one the targeted detection at 99.7% CL. The spectra have been estimated masking the regions most contaminated by foregrounds for a final f_sky of 12%.