Notes. Columns: (1) Name of the galaxy; systems are marked with the relative position to each other (e.g. N, S, E, W). (2) Square kpc of the area corresponding to flat radio spectral index (α ≤ 0.5) in the α-maps. The errors were calculated by taking into account the error per pixel as shown in the error α-maps. Values in parenthesis are upper limits, while square brackets denote unresolved sources. (3) Fraction of the flat area to the total area marked by the α-map (Fig. 2). (4) Size of area of mid-IR emission at 13.2 μm in kpc²; the calculation method is described in Diaz-Santos et al. (2010b); values in parenthesis denote upper limits, meaning the measured size is < 10% larger than the instrumental size (PSF) so an intrinsic size for the emitting region couldn’t be calculated. The reported upper limits are on the measured size (not intrinsic), i.e. 1.1×PSF size. For objects marked with ’—’ there is no available measurement. Note: IRAS F12112+0305 and IRAS F14348-1447 are double radio sources but their radio components are not completely separated. IRAS F17132+5313 1has two radio components, separated, but the infrared source is barely separated. NGC 5256 (SW) and (C) are barely separated at 1.49 GHz (see α-map). Here we give the flat area of the SW radio component which is associated with the most luminous infrared source. The total flat area of NGC 5256 (SW) and (C) is 5.10 kpc². We put a limit on NGC5256 (C) because the area is partly overlapping with the southernmost component.