The Astrophysical Journal (Jan 2023)

Formation Mechanism of Laser-driven Magnetized “Pillars of Creation”

  • Zhu Lei,
  • Lifeng Wang,
  • Jiwei Li,
  • Shiyang Zou,
  • Junfeng Wu,
  • Zhonghai Zhao,
  • Wei Sun,
  • Wenqiang Yuan,
  • Longxing Li,
  • Zheng Yan,
  • Jun Li,
  • Wenhua Ye,
  • Xiantu He,
  • Bin Qiao

DOI
https://doi.org/10.3847/1538-4357/ace7b6
Journal volume & issue
Vol. 954, no. 2
p. 130

Abstract

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The Pillars of Creation, one of the most recognized objects in the sky, are believed to be associated with the formation of young stars. However, so far, the formation and maintenance mechanism of the pillars are still not fully understood due to the complexity of the nonlinear radiation magnetohydrodynamics (RMHD). Here, assuming laboratory laser-driven conditions, we studied the self-consistent dynamics of pillar structures in magnetic fields by means of two-dimensional and three-dimensional (3D) RMHD simulations, and the results support our proposed experimental scheme. We find that only when the magnetic pressure and ablation pressure are comparable, the magnetic field can significantly alter the plasma hydrodynamics. For medium-magnetized cases ( β _initial ≈ 3.5), the initial magnetic fields undergo compression and amplification. This amplification results in the magnetic pressure inside the pillar becoming large enough to support the sides of the pillar against radial collapse due to pressure from the surrounding hot plasma. This effect is particularly pronounced for the parallel component ( B _y ), which is consistent with observational results. In contrast, a strong perpendicular ( B _x , B _z ) magnetic field ( β _initial < 1) almost retains its initial distribution and significantly suppresses the expansion of blown-off gas plasma, leading to the inability to form pillar-like structures. The 3D simulations suggest that the bending at the head of “Column I” in the Pillars of Creation may be due to nonparallel magnetic fields. After similarity scaling transformation, our results can be applied to explain the formation and maintenance mechanism of the pillars, and can also provide useful information for future experimental designs.

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