Radio maps of the A399-401 system at lower resolutions. Left panel: resolution of 24.6″ × 27.1″ with σ = 230 μJy beam⁻¹. Right panel: resolution 72.8″ × 75.9″ with σ = 809 μJy beam⁻¹. The dark blue brightness depression (BD) and the halo extension (HE) are described in the text. The beam size in all images is given in the lower left corner, and the scale of 1 Mpc at z = 0.072 is given in the upper left corner. The square-root color scale of the images extends from 0 to 25σ.