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The collapse of slowly rotating molecular cloud cores threaded by magnetic fields is investigated by high-resolution numerical simulation. Outflow formation in the collapsing cloud cores is also followed. In the models examined, the cloud core and parent cloud rotate rigidly and are initially threaded by a uniform magnetic field. The simulations show that the cloud core collapses along the magnetic field lines. The magnetic field in the dense region of the cloud core rotates faster than that of the parent cloud as a consequence of spin-up of the central region during the collapse. The cloud core exhibits significant precession of the rotation axis, magnetic field, and disk orientation, with precession highest in the models with low initial field strength ($lesssim 20 mu {rm G}$). Precession in models with initial fields of $sim 40 mu {rm G}$ is suppressed by strong magnetic braking. Magnetic braking transfers angular momentum form the central region and acts more strongly on the component of angular momentum oriented perpendicular to the magnetic field. After the formation of an adiabatic core, outflow is ejected along the local magnetic field lines. Strong magnetic braking associated with the outflow causes the direction of angular momentum to converge with that of the local magnetic field, resulting in the convergence of the local magnetic field, angular momentum, outflow, and disk orientation by the outflow formation phase. The magnetic field of a young star is inclined at an angle of no more than $30^circ$ from that of the parent cloud at initial field strengths of $sim 20 mu {rm G}$, while at an initial field strength of $sim 40 mu {rm G}$, the magnetic field of the young star is well aligned with that of the parent cloud.
We estimate the polarized thermal dust emission from MHD simulations of protostellar collapse and outflow formation in order to investigate alignment of outflows with magnetic fields. The polarization maps indicate that alignment of an outflow with t
We present results of 1.3 mm dust polarization observations toward 16 nearby, low-mass protostars, mapped with ~2.5 resolution at CARMA. The results show that magnetic fields in protostellar cores on scales of ~1000 AU are not tightly aligned with ou
We investigate the formation of circumstellar disks and outflows subsequent to the collapse of molecular cloud cores with the magnetic field and turbulence. Numerical simulations are performed by using an adaptive mesh refinement to follow the evolut
Low-energy cosmic rays are the dominant source of ionization for molecular cloud cores. The ionization fraction, in turn, controls the coupling of the magnetic field to the gas and hence the dynamical evolution of the cores. The purpose of this work
By studying 7 objects in the Lupus clouds we aim to test if a coherence exists between commonly used evolutionary tracers. We present ALMA observations of the continuum and molecular line emission that probe the dense gas and dust of cores and thei