Panel (a): Best-fit MF power spectrum, ranging between Λ_min = 7 kpc (k_max = 413) and Λ_max = 470 kpc (k_min = 6), with peak at ∼140 kpc (C = 10.1 Mpc⁻¹, k ∼ 20). Panel (b): Profile of ⟨B⟩ as a function of the projected distance from the cluster centre. It is the mean over five simulations and the scatter is the standard deviation. The central average MF, ⟨B₀⟩, is equal to 9.5 ± 1.0 μG. Dashed pink line represents the MF fluctuations taken along the central LOS.