  Non-ideal magnetohydrodynamics (MHD) is the dominant process. We investigate
the effect of magnetic fields (ideal and non-ideal) and turbulence (sub- and
transsonic) on the formation of protostars by following the gravitational
collapse of 1~M$_\odot$ gas clouds through the first hydrostatic core to
stellar densities. The clouds are imposed with both rotational and turbulent
velocities, and are threaded with a magnetic field that is
parallel/anti-parallel or perpendicular to the rotation axis; we investigate
two rotation rates and four Mach numbers. The initial radius and mass of the
stellar core are only weakly dependent on the initial parameters. In the models
that include ideal MHD, the magnetic field strength implanted in the protostar
at birth is much higher than observed, independent of the initial level of
turbulence; only non-ideal MHD can reduce this strength to near or below the
observed levels. This suggests that not only is ideal MHD an incomplete picture
of star formation, but that the magnetic fields in low mass stars are implanted
later in life by a dynamo process. Non-ideal MHD suppresses magnetically
launched stellar core outflows, but turbulence permits thermally launched
outflows to form a few years after stellar core formation.
