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We carry out 3D MHD simulations of star formation in turbulent,
magnetized clouds, including ambipolar diffusion, star formation, and
feedback from protostellar outflows. The calculations focus
on a parameter regime where the magnetic field is strong enough
to resist severe tangling by turbulent motions and to retard global
gravitational contraction in the cross-field direction. They are
motivated by observations of the Taurus molecular cloud complex,
which show a well-ordered magnetic field on the large scale,
and elongated condensations more or less perpendicular to the
large-scale field. We find that stars form in earnest in such
magnetically dominated clouds when enough material has settled
gravitationally along the field lines that the mass-to-flux
ratios of the condensations approach the critical value.
Only a small fraction (of order $1\%$ or less) of the nearly
magnetically-critical, condensed material is turned into stars
per local free-fall time, however.
Dense cores formed in our simulations are typically triaxial,
although more massive cores tend to be more oblate.
The external turbulent pressure is dynamically important to bound the cores,
in particular, for less massive cores.
The specific angular momentum peaks at around 10^21 cm^2 s^{-1}, in good
agreement with observations of starless dense cores. The core mass function
resembles the Salpeter IMF.
It flattens near the characteristic Jeans mass of the condensed material,
which is a few solar masses for typical parameters.
Formation of dense cores is likely to be regulated primarily by magnetic field,
instead of turbulence, at least for regions like the Taurus molecular clouds
and pipe nebula, since the condensed material tends to be more or
less quiescent. In such regions, magnetically regulated gravitational
fragmentation, instead of turbulent fragmentation, is likely to be a
leading mechanism for core formation.
In our paper, we present more detailed analysis of core properties.
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