The impact of the Hall effect during cloud core collapse:implications for circumstellar disk evolution [SSA]

http://arxiv.org/abs/1706.04363


We perform three-dimensional radiation non-ideal magnetohydrodynamics simulations and investigate the impact of the Hall effect on the angular momentum evolution in the collapsing cloud cores in which the magnetic field $\mathbf{B}$ and angular momentum $\mathbf{J_{\rm ang}}$ are misaligned each other. We find that the Hall effect notably changes the magnetic torques in the pseudo-disk, and strengthens and weakens the magnetic braking in cores with an acute and obtuse relative angles between $\mathbf{B}$ and $\mathbf{J_{\rm ang}}$, respectively. This suggests that the bimodal evolution of the disk size may appear in Class 0 young stellar objects (YSOs) even if $\mathbf{B}$ and $\mathbf{J_{\rm ang}}$ are randomly distributed. We show that a counter-rotating envelope form in the upper envelope of the pseudo-disk in cloud cores with obtuse relative angles. We also find that a counter-rotating region forms at the midplane of the pseudo-disk in cloud cores with acute relative angles. The former and latter types of counter-rotating envelopes may be associated with the YSOs with a large ($r\sim100$ AU) and small ($r\lesssim10$ AU) disks, respectively.

Read this paper on arXiv…

Y. Tsukamoto, S. Okuzumi, K. Iwasaki, et. al.
Thu, 15 Jun 17
50/68

Comments: 20 pages, 17 figures, submitted to PASJ. comments are welcome