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Using hydrodynamic simulations we investigate the rotational properties and angular momentum evolution of prestellar and protostellar cores formed from gravoturbulent fragmentation of interstellar gas clouds. We find the specific angular momentum j of prestellar cloud cores in our models to be on average comparable to the observed values. A fraction of prestellar cores is gravitationally unstable and goes into collapse to build up protostars and protostellar systems. Their specific angular momentum is one order of magnitude lower than their parental cores and in agreement with observations of main-sequence binaries. The ratio of rotational to gravitational energy of protostellar cores in the model turns out to be very similar to the observed values. We find, that it is roughly conserved during the main collapse phase. This leads to j proportional to M^{2/3}, where j is specific angular momentum and M core mass. Although the temporal evolution of the angular momentum of individual protostars or protostellar systems is complex and highly time variable, this correlation holds well in a statistical sense for a wide range of turbulent environmental parameters. In addition, high turbulent Mach numbers result in the formation of more numerous protostellar cores with, on average, lower mass. Therefore, models with larger Mach numbers result in cores with lower specific angular momentum. We find, however, no dependence on the spatial scale of the turbulence. Our models predict a close correlation between the angular momentum vectors of neighboring protostars during their main accretion phase. Possible observational signatures are aligned disks and parallel outflows. The latter are indeed observed in some low-mass isolated Bok globules.
[abridged] Understanding how the infalling gas redistribute most of its initial angular momentum inherited from prestellar cores before reaching the stellar embryo is a key question. Disk formation has been naturally considered as a possible solution
(abridged version) Identifying the processes that determine the initial mass function of stars (IMF) is a fundamental problem in star formation theory. One of the major uncertainties is the exact chemical state of the star forming gas and its influen
The formation and collapse of a protostar involves the simultaneous infall and outflow of material in the presence of magnetic fields, self-gravity, and rotation. We use self-similar techniques to self-consistently model the anisotropic collapse and
Identifying the processes that determine the initial mass function of stars (IMF) is a fundamental problem in star formation theory. One of the major uncertainties is the exact chemical state of the star forming gas and its influence on the dynamical
We have analyzed high resolution N-body simulations of dark matter halos, focusing specifically on the evolution of angular momentum. We find that not only is individual particle angular momentum not conserved, but the angular momentum of radial shel