Left: radio (red circles) and X-ray (blue triangles) surface brightness radial profiles within the halo region, normalised at their maximum. The source-subtracted LOFAR map at 19″ × 15″ resolution sampled with concentric annuli of 19″ width is shown in the corner. Right: point-to-point analysis of the I_R − I_X relation. In the corner, we report the contours of the 30″ × 30″ source-subtracted LOFAR map, gridded with green and red 30″ × 30″ square boxes for the relic and halo, respectively. The halo points present a sub-linear correlation with a slope in the range [0.42–0.60]. The black line represents the best fit obtained with the BCES-orthogonal method at 3σ threshold.