Presentation #202.10 in the session Star Formation.
The star formation rate per free-fall time, εff, is predicted in theories of turbulence-regulated star formation to be low and relatively constant. We follow up on previous analyses by computing εff in nearby molecular clouds using observed protostars (from the SESNA database) and cloud properties (from the HOTT analysis of Herschel observations and from molecular line observations in the GAS and KEYSTONE surveys). While we are able to reproduce the cloud-scale Kennicutt-Schmidt law and εff estimates from previous analyses, we find that an excess scatter in εff correlates with properties of the local cloud environment. Examining 155 individual clumps identified within the cloud data, we find that εff correlates strongly with the clump mass, average density, and virial parameter (Spearman test statistic p<0.001). εff shows some correlation with the presence of OBA stars, but not strongly enough to explain the other relations. We are investigating possible biases introduced by incompleteness and crowding.