Context. In the context of star and planet formation, understanding the formation of disks is of fundamental importance. Aims. Previous studies found that the magnetic field has a verystrong impact on the collapse of a prestellar cloud, by possiblysuppressing the formation of a disk even for relatively modest valuesof the magnetic intensity. Since observations infer that cores have asubstantial level of magnetization, this raises the question of howdisks form. However, most studies have been restricted to the case inwhich the initial angle, ,between the magnetic field and the rotation axis equals 0.Here we explore and analyse the influence of non aligned configurations on disk formation. Methods. We perform 3Dideal MHD, AMR numerical simulations for various values of,the ratio of the mass-to-flux to the critical mass-to-flux, and various values of.Results. We find that disks form more easily as increases from 0 to 90.We propose that as the magnetized pseudo-disks become thicker with increasing ,the magnetic braking efficiency is lowered. We also find that even small values of (10-20)show significant differences with the aligned case. Conclusions. Within the framework of ideal MHD, and for ourchoice of initial conditions, centrifugally supported disks cannot formfor values ofsmaller than 3 when the magnetic field and the rotation axis are perpendicular, and smaller than about 5-10 when they are perfectly aligned. Key words: magnetohydrodynamics (MHD) - instabilities - ISM:kinematics and dynamics - ISM: clouds - ISM: structure - star: formation
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