Effect of Angular Momentum Alignment and Strong Magnetic Fields on the
  Formation of Protostellar Disks
  Star forming molecular clouds are observed to be both highly magnetized and
turbulent. Consequently the formation of protostellar disks is largely
dependent on the complex interaction between gravity, magnetic fields, and
turbulence. Studies of non-turbulent protostellar disk formation with realistic
magnetic fields have shown that these fields are efficient in removing angular
momentum from the forming disks, preventing their formation. However, once
turbulence is included, disks can form in even highly magnetized clouds,
although the precise mechanism remains uncertain. Here we present several high
resolution simulations of turbulent, realistically magnetized, high-mass
molecular clouds with both aligned and random turbulence to study the role that
turbulence, misalignment, and magnetic fields have on the formation of
protostellar disks. We find that when the turbulence is artificially aligned so
that the angular momentum is parallel to the initial uniform field, no
rotationally supported disks are formed, regardless of the initial turbulent
energy. We conclude that turbulence and the associated misalignment between the
angular momentum and the magnetic field are crucial in the formation of
protostellar disks in the presence of realistic magnetic fields.
