EPoS Contribution
EPoS Contribution
New tests of the role of magnetic fields in star forming regions

Wolf Dapp
University of Western Ontario, London, Canada
Recent advances in numerical simulations yield a wealth of information, and invite detailed comparisons with data from current and future instruments. Our MHD simulations give us access to a wide range of initial conditions for the onset of molecular cloud fragmentation, probing the effect of magnetic fields, turbulence, and ambipolar diffusion. We confront results from our models with observed column density profiles from B68 and L1689B. An important result is that any inferred steepening of embedded cores cannot be explained by a transition from a magnetically supercritical core to a subcritical envelope. We propose that the amount of magnetic field line curvature provides a quantitative and more conclusive test of the importance of the magnetic field; in general, weaker fields lead to stronger curvature. This method is applied to high mass star formation regions such as OMC-1 and DR21(OH), where field line curvature data is available. High-resolution polarization maps and density profiles by e.g. SMA, Herschel, and ALMA will provide important tests for the predictions made by our models.