Turbulence-induced disc formation in strongly magnetised cloud cores
  We present collapse simulations of strongly magnetised, turbulent molecular
cloud cores with masses ranging from 2.6 to 1000 M_sun in order to study the
influence of the initial conditions on the turbulence-induced disc formation
mechanism proposed recently by Seifried et al. 2012. We find that Keplerian
discs are formed in all cases independently of the core mass, the strength of
turbulence, or the presence of global rotation. The discs appear within a few
kyr after the formation of the protostar, are 50 - 150 AU in size, and have
masses between 0.05 and a few 0.1 M_sun. During the formation of the discs the
mass-to-flux ratio stays well below the critical value of 10 for Keplerian disc
formation. Hence, flux-loss alone cannot explain the formation of Keplerian
discs. The formation of rotationally supported discs at such early phases is
rather due to the disordered magnetic field structure and due to turbulent
motions in the surroundings of the discs, two effects lowering the classical
magnetic braking efficiency. Binary systems occurring in the discs are mainly
formed via the disc capturing mechanism rather than via disc fragmentation,
which is largely suppressed by the presence of magnetic fields.
