Analysis of the radio emission of G113. Left: spectral index map of the cluster G113, with LOFAR contours of the image at 35″ × 35″ overplotted ([−3, 3, 6, 9, 12] × σ, with σ = 0.37 mJy beam⁻¹). Centre: uGMRT image of G113, with LOFAR contours overplotted. The resolution of the image is 35″ × 35″ and the rms noise is σ = 0.037 mJy beam⁻¹. Right top: distribution of the spectral index extracted from square-shaped boxes of width 35″ in the halo (grey) and southern relic (orange) regions. The vertical lines represent the α median values for the halo (black) and relic (orange). Right bottom: values of α extracted from the sector shown in the subplot. The sectors are numbered from the outer annulus (1) to the inner one (4).