In search of evidence for protostellar collapse - A systematic study of line formation in low-mass dense cores

Radiative transfer models of low-mass dense cores as depicted in two theoretical models of protostellar collapse, the Larson-Penston flow and the theory of Shu and coworkers based on the «inside-out collapse» model, are presented. In particular, line profiles of the first three rotational transitions of the CS molecule are calculated for hypothetical dense cores evolving according to these theories. The results are compared with CS observations of nearby dense cores. It is shown that the Larson-Penston flow overestimates the velocity width of the CS lines by a large margin and cannot be reconciled with the observations