The angular momentum of dense clumps in elephant trunks

Abstract

The radiation from newly born massive stars photoionize and erode the parental molecular cloud, producing structures such as the so-called elephant trunks. At the head of an elephant trunk, the interaction of theshock (driven by the photo evaporation process) with previously existing density perturbations leads to the formation of dense clumps. Some of these clumps have enough mass to be auto-gravitating, and therefore can eventually form new stars. We carry out a 3D simulation of this process, and from the results we compute the angular momenta of these collapsing clumps. We show that the angular momenta of the clumps have preferential directions, which in principle indicate the directions in which jets will eventually be ejected from the star+accretion disk systems that will be formed.