Larson relations in massive clumps

The clumps are divided into five evolutionary stages so that we can also discuss the Larson relations as a function of evolution. We show that this ensemble does not follow the three Larson relations, regardless of the clump's evolutionary phase.

A consequence of this breakdown is that the dependence of the virial parameter {alpha}_vir_ on mass (and radius) is only a function of the gravitational energy, independent of the kinetic energy of the system; thus, {alpha}_vir_ is not a good descriptor of clump dynamics. Our results suggest that clumps with clear signatures of infall motions are statistically indistinguishable from clumps with no such signatures. The observed non-thermal motions are not necessarily ascribed to turbulence acting to sustain the gravity, but they might be a result of the gravitational collapse at the clump scales.