Contributions calculated in the stochastic (solid) and equilibrium (dashed) regimes to the total emissivity (dotted) for each of the grain types silicate (magenta), graphite (green), and PAHs (blue), by one of our codes (DIRTY). The panels show the results for a selection of the input fields defined in Sect. 3. For the scaled Mathis input fields, the emissivity is divided by the input field strength U to allow identical axis ranges for all plots. The relative contributions for each regime may vary between codes because of the differences in the schemes to transition from one regime to the other.