Example of a Faraday spectrum given in the polarised intensity for the 009 observation (blue line) and the reference (014) observation at a randomly chosen location marked with a blue circle in Fig. 4 (RA 242°18′03.60″ and Dec 56°08′16.80″), given on the left panel. Calculated modulus of the complex cross-correlation function |ζ| (red line) for the given Faraday spectra, fitted with a Gaussian (blue dashed line) to estimate the misalignment between the two observations (black vertical line) at this specific location, given on the right panel.