Modelling Herschel observations of infrared-dark clouds in the Hi-GAL survey

We demonstrate the use of the 3D Monte Carlo radiative transfer code phaethon to model infrared-dark clouds (IRDCs) that are externally illuminated by the interstellar radiation field (ISRF). These clouds are believed to be the earliest observed phase of high-mass star formation, and may be the high-mass equivalent of lower mass pre-stellar cores. We model three different cases as examples of the ...