Simulated emission maps at 15 GHz (left panel) and at 100 GHz (right panel) with beam sizes of 0.13″ × 0.13″ and 0.042″ × 0.042″, respectively. The forward interaction structure is a bright arc. The black dot shows the position of the IBH, and the green left-arrow shows its direction of motion. The black contour levels are at 50, 100, 200 and 300 μJy beam⁻¹ in the left panel, and at 10 and 50 μJy beam⁻¹ in the right panel.