Reference solutions generated with the public version of DustEM (see Sect. 5.1) using 3500 temperature bins and 250 iterations in the integral equation solver. The panels show the calculated dust emissivity for a selection of the input fields defined in Sect. 3. In each panel, the red curve represents the total emissivity and the other curves represent the portion of the emissivity for each grain type, silicate (magenta), graphite (green), and PAHs (blue). For the scaled Mathis input fields, the emissivity is divided by the input field strength U to allow identical axis ranges for all plots.