The Super-Alfvénic Model of Molecular Clouds: Predictions for Zeeman Splitting Measurements

We present synthetic OH Zeeman splitting measurements of a super-Alfvénic molecular cloud model. We select dense cores from synthetic 13 CO maps computed from the largest simulation to date of supersonic and super-Alfvénic turbulence. The synthetic Zeeman splitting measurements in the cores yield a relation between the magnetic field strength, B , and the column density, N , in good agreement with the observations. The large scatter in B at a fixed value of N is partly due to intrinsic variations in the magnetic field strength from core to core. We also compute the relative mass-to-flux ratio between the center of the cores and their envelopes, , and show that super-Alfvénic turbulence produces a significant scatter also in , including negative values (field reversal between core center and envelope). We find for 70% of the cores, and for 12%. Of the cores with | B LOS | > 10 μG, 81% have . These predictions of the super-Alfvénic model are in stark contrast to the ambipolar drift model of core formation, where only is allowed.