Influence of the magnetic field on the formation of protostellar disks
  We numerically model the collapse of magnetic rotating protostellar clouds
with mass of 10 $M_{sun}$. The simulations are carried out with the help of 2D
MHD code Enlil. The structure of the cloud at the isothermal stage of the
collapse is investigated for the cases of weak, moderate, and strong initial
magnetic field. Simulations reveal the universal hierarchical structure of
collapsing protostellar clouds, consisting of flattened envelope with the
qausi-magnetostatc disk inside and the first core in its center. The size of
the primary disk increases with the initial magnetic energy of the cloud. The
magnetic braking efficiently transports the angular momentum from the primary
disk into the envelope in the case, when initial magnetic energy of the cloud
is more than 20 % of its gravitational energy. Intensity of the outflows
launched from the region near the boundary of the first core increases with
initial magnetic energy. The `dead' zone with small ionization fraction,
$x<10^{-11}$, forms inside the first hydrostatic core and at the base of the
outflow. Ohmic dissipation and ambipolar diffusion determine conditions for
further formation of the protostellar disk in this region.
