EPoS Contribution
EPoS Contribution
Constraining the Environment of Star-Forming Regions: From Observations to Simulations and Back Again

Helen Kirk
University of Victoria / Herzberg Institute of Astrophysics, Victoria, Canada
With the advent of large (degree) scale surveys of molecular clouds in dust continuum, molecular lines, and extinction, the (column) density and kinematic structure of star forming regions can now be studied. Numerical simulations have also advanced to the point where a study of the parameter space of the initial conditions can be explored. I will first highlight the observed constraints on the physical conditions for dense cores formation:
(1) the cores are dominated by thermal motions but live within a larger envelope that is much more turbulent,
(2) the connection between the core and its larger environment is not very dynamical, and
(3) the velocity dispersion of the the cores within a single part of the molecular cloud appear sub-virial.

I will then discuss recent work analyzing a suite of 2D turbulent MHD simulations of star formation and the calculated 'observations' in order to compare the simulations with real regions: most models produce thermally dominated cores but it is much more difficult to produce a strongly turbulent low density environment where cores share the dynamics of their nearby surroundings. The differing dynamical behaviours theoretically expected for cores and their environments will also be briefly discussed, focusing on the interplay between turbulence and magnetic fields, and the possible importance of driven turbulence. Finally, I will conclude with a look to the future and the advances expected with the next generation of large-scale surveys of molecular clouds scheduled for the next few years.