For high-redshift submillimetre or millimetre sources detected with single dish telescopes , interferometric follow-up has shown that many are multiple submm galaxies blended together .
Confusion-limited Herschel observations of such targets are also available , and these sample the peak of their spectral energy distribution in the far-infrared .
Many methods for analysing these data have been adopted , but most follow the traditional approach of extracting fluxes before model spectral energy distributions are fit , which has the potential to erase important information on degeneracies among fitting parameters and glosses over the intricacies of confusion noise .
Here , we adapt the forward-modelling method that we originally developed to disentangle a high-redshift strongly-lensed galaxy group , in order to tackle this problem in a more statistically rigorous way , by combining source deblending and SED fitting into the same procedure .
We call this method “ SEDeblend. ” As an application , we derive constraints on far-infrared luminosities and dust temperatures for sources within the ALMA follow-up of the LABOCA Extended Chandra Deep Field South Submillimetre Survey .
We find an average dust temperature for an 870 \mu m-selected sample of ( 33.9 \pm 2.4 ) K for the full survey .
When selection effects of the sample are considered , we find no evidence that the average dust temperature evolves with redshift .