We investigate protostellar collapse of molecular cloud cores by numericalsimulations, taking into account turbulence and magnetic fields. By using theadaptive mesh refinement technique, the collapse is followed over a widedynamic range from the scale of a turbulent cloud core to that of the firstcore. The cloud core is lumpy in the low density region owing to theturbulence, while it has a smooth density distribution in the dense regionproduced by the collapse. The shape of the dense region depends mainly on themass of the cloud core; a massive cloud core tends to be prolate while a lessmassive cloud core tends to be oblate. In both cases, anisotropy of the denseregion increases during the isothermal collapse. The minor axis of the denseregion is always oriented parallel to the local magnetic field. All the modelseventually yield spherical first cores supported mainly by the thermalpressure. Most of turbulent cloud cores exhibit protostellar outflows aroundthe first cores. These outflows are classified into two types, bipolar andspiral flows, according to the morphology of the associated magnetic field.Bipolar flow often appears in the less massive cloud core. The rotation axis ofthe first core is oriented parallel to the local magnetic field for bipolarflow, while the orientation of the rotation axis from the global magnetic fielddepends on the magnetic field strength. In spiral flow, the rotation axis isnot aligned with the local magnetic field.
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