EPoS Contribution
EPoS Contribution
Comparing different molecular cloud formation mechanisms and subsequent evolution.

Jonathan Carroll-Nellenback
University of Rochester, Rochester, NY, USA
Molecular Clouds are the birth place of stars, yet fundamental questions as to their origin remain unresolved. Do they form from colliding flows, or do they condense out of the background ISM? Is their observed velocity line-widths due to a turbulent cascade of initial and/or externally driven kinetic energy, or is it the result of gravitational collapse? Here we compare the results of various simulations of cloud formation with observed cloud properties to constrain formation mechanisms. Using 3-D AMR multi-physics calculations via the code AstroBEAR we carry forward a series of simulations which allow us to compare and contrast three mechanisms for the generation of turbulence: colliding large scale flows which both form the clouds and seed their turbulent motions; internal driving of turbulent motions via interacting stellar outflows; gravitationally induced turbulence driven by collapse on multiple scales. As part of our comparison we also will discuss how different mechanisms move kinetic energy from large to small scales and characterize how both gravitational and outflow driven cascades are different from more traditional models.
A. Frank, Univ. of Rochester, USA
E. Blackman, Univ. or Rochester, USA
F. Heitsch, Univ. of North Carolina, USA