Smoothed observed bispectrum as determined with the binned estimator divided by its expected standard deviation, as a function of ℓ₁ and ℓ₂, with ℓ₃ in the bin [610, 654]. From left to right on the top row are shown: SMICA, NILC, and SEVEM; and on the bottom row: C-R and the raw 143 GHz channel. For comparison purposes the last figure on the bottom row shows the same quantity for one of the lensed Gaussian simulations described in Sect. 6.2.