Rest-frame spectral energy distribution (SED) of our sample. The light blue data points represent the UV-IR photometry that was used for the SED fitting (Circosta et al. 2018). The red point shows our ALMA Band 7 flux measurements, which was also included in the fit. The violet point in cid_451 shows the ALMA Band 3 flux from Circosta et al. (2021). The blue, orange, and pink points show the radio fluxes at 1.4, 3, and 5 GHz, respectively. The arrows indicate 3σ upper limits. The solid curves show the results of the SED fitting with CIGALE: in black is the total best-fit model (including the contribution the from nebular emission component), in orange the dust-attenuated stellar emission, in magenta the emission from dust heated by star formation and in green the emission from dust heated by the AGN. To estimate the maximum contribution of synchrotron emission to the rest-frame 260 μm flux density we parameterized this emission as a power law with spectral index α_r (dashed red line), normalised at 3 GHz (10cm) or 1.4 GHz (21cm), depending on the available radio data. For the galaxies with radio fluxes in two bands, we derived α_r based on the two fluxes. On the plot we show the estimated contribution (in percentage) from dust heated by the AGN and from synchrotron emission to the rest-frame 260 μm ALMA Band 7 flux, estimated from the total SED template.