English

Formation of unipolar outflow and $\textit{protostellar rocket effect}$ in magnetized turbulent molecular cloud cores

Solar and Stellar Astrophysics 2024-01-08 v1 Earth and Planetary Astrophysics Astrophysics of Galaxies

Abstract

Observed protostellar outflows exhibit a variety of asymmetrical features, including remarkable unipolar outflows and bending outflows. Revealing the formation and early evolution of such asymmetrical protostellar outflows, especially the unipolar outflows, is essential for a better understanding of the star and planet formation because they can dramatically change the mass accretion and angular momentum transport to the protostars and protoplanetary disks. Here, we perform the three-dimensional non-ideal magnetohydrodynamics simulations to investigate the formation and early evolution of the asymmetrical protostellar outflows in magnetized turbulent isolated molecular cloud cores. We find, for the first time to our knowledge, that the unipolar outflow forms even in the single low-mass protostellar system. The results show that the unipolar outflow is driven in the weakly magnetized cloud cores with the dimensionless mass-to-flux ratios of μ=8\mu=8 and 1616. Furthermore, we find the protostellar rocket effect\textit{protostellar rocket effect} of the unipolar outflow, which is similar to the launch and propulsion of a rocket. The unipolar outflow ejects the protostellar system from the central dense region to the outer region of the parent cloud core, and the ram pressure caused by its ejection suppresses the driving of additional new outflows. In contrast, the bending bipolar outflow is driven in the moderately magnetized cloud core with μ=4\mu=4. The ratio of the magnetic to turbulent energies of a parent cloud core may play a key role in the formation of asymmetrical protostellar outflows.

Keywords

Cite

@article{arxiv.2401.02525,
  title  = {Formation of unipolar outflow and $\textit{protostellar rocket effect}$ in magnetized turbulent molecular cloud cores},
  author = {Daisuke Takaishi and Yusuke Tsukamoto and Miyu Kido and Shigehisa Takakuwa and Yoshiaki Misugi and Yuki Kudoh and Yasushi Suto},
  journal= {arXiv preprint arXiv:2401.02525},
  year   = {2024}
}

Comments

24 pages, 6 figures, accepted for publication in ApJ