Ralf Launhardt


The temperature and density structure of isolated low-mass cores

Stutz, Lippok, Schmalzl, Krause, Balog, Beuther, Henning, Kainulainen, Linz, Nielbock, Ragan, Schmiedeke


The evolution of the density structure of a star-forming cloud core is one of the key aspects in protostellar collapse models. However, ground-based submm observations provide only poor constraints on the low temperatures in such regions, such that density profile estimates often rely on simplifying assumptions of the temperature structure or weakly constrained radiative transfer models. We have used the Herschel bolometers as thermometers to measure with unprecedented accuracy the dust temperature structure of low-mass star-forming cores. For this purpose, we selected 14 small, nearby, and well-isolated molecular clouds and obtained deep continuum maps with PACS and SPIRE within the framework of our EPOS GTKP. I will give an overview of our method to reconstruct the dust temperature and density maps, derive constraints on dust properties, and show results that demonstrate the effects of external heating, shielding, and central cooling, and how this affects the derivation of density profiles. In ongoing work, these results are combined with molecular line observations to study the relation between temperature, density, gas phase abundances, and grain properties.