a given L(FIR), the local galaxy population exhibits a distribution in 60–100 colour or, equivalently, dust temperature, as characterised by Chapin et al. (2009). We use this distribution (Chapin et al. 2009, equations 8 and 9) to assign each star-forming galaxy a 60–100 colour, $C$, defined as the ratio of the rest-frame monochromatic 60 and 100 flux densities: $C = \rm{log} L_{\rm{60}}/L_{\rm{100}}$. The template nearest in colour is then selected from the Rieke library using the empirical $C$–L(TIR) conversion for these templates shown in Fig. \[fig:RiekeCOLOR\], for which a functional fit is:

$$C = 0.33 \rm{tanh}[1.1(\rm{log L(TIR)} - 11.0)] - 0.23.$$

Having selected the template shape from the Rieke library by this process, the final step is to normalise it to actual value of L(FIR) originally specified by the far-infrared–radio relation. This is done using the non-linear L(FIR)–L(TIR) relation given in Fig. \[fig:LTIRtoFIR\_Rieke\]. Chaplin et al. (2009) presented evidence for evolution in the colour-luminosity relation, but we initially assume that the local relation applies at all redshifts.

![The symbols show the far-infrared luminosity (42.5–122.5 ), L(FIR)(), of the star-forming galaxy templates of Rieke et al. (2009) as a function of total infrared luminosity, L(TIR). To assign SED templates to the 