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arXiv · 2403.15280

Polarization Holes as an Indicator of Magnetic Field-Angular Momentum Alignment I. Initial Tests

Lijun Wang·Zhuo Cao·Xiaodan Fan·Hua-bai Li
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Abstract

The formation of protostellar disks is still a mystery, largely due to the difficulties in observations that can constrain theories. For example, the 3D alignment between the rotation of the disk and the magnetic fields (B-fields) in the formation environment is critical in some models, but so far impossible to observe. Here, we study the possibility of probing the alignment between B-field and disk rotation using ``polarization holes'' (PHs). PHs are widely observed and are caused by unresolved B-field structures. With ideal magnetohydrodynamic (MHD) simulations, we demonstrate that different initial alignments between B-field and angular momentum (AM) can result in B-field structures that are distinct enough to produce distinguishable PHs. Thus PHs can potentially serve as probes for alignments between B-field and AM in disk formation.

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Lijun Wang, Zhuo Cao, Xiaodan Fan, Hua-bai Li. 2024-03-22. Polarization Holes as an Indicator of Magnetic Field-Angular Momentum Alignment I. Initial Tests. https://arxiv.org/abs/2403.15280

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