Chapter

Jet Driven Turbulence?

DOI: 10.1007/978-3-642-00576-3_50

ABSTRACT Molecular clouds, the birth sites of stars, are permeated by supersonic gas motions. Here, we summarize our results from numerical
simulations on individual jets interacting with their ambient medium. These single jet simulations show that the volume filling
factor of supersonic turbulence excited by jets is very low. In general, supersonic motions, if driven at small scales, do
not propagate far from their source and are damped quickly. Therefore, it is unlikely that the supersonic motions observed
in molecular clouds are maintained by jets launched from protostellar objects. Our preliminary results from three dimensional
simulations of collapsing cloud cores with a self-consistent description of mechanical feedback around protostellar objects
point towards the same results.

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