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arXiv · 1808.00276

The formation of `columns crowns' by jets interacting with a circumstellar dense shell

Muhammad Akashi·Noam Soker
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Abstract

We conduct three-dimensional hydrodynamical simulations of two opposite jets that interact with a spherical slow wind that includes a denser shell embedded within it, and obtain a bipolar nebula where each of the two lobes is composed of two connected bubbles and Rayleigh-Taylor instability tongues that protrude from the outer bubble and form the `columns crown'. The jets are launched for a short time of 17 years and inflate a bipolar nebula inside a slow wind. When the bipolar structure encounters the dense shell, the interaction causes each of the two lobes to split to two connected bubbles. The interaction is prone to Rayleigh-Taylor instabilities that form tongues that protrude as columns from the outer bubble. The bases of the columns form a ring on the surface of the outer bubble, and the structure resemble a crown that we term the columns crown. This structure resembles, but is not identical to, the many filaments that protrude from the lobes of the bipolar planetary nebula Menzel~3. We discuss our results in comparison to the structure of Menzel~3 and the ways by which the discrepancies can be reconciled, and possibly turn our failure to reproduce the exact structure of Menzel~3 to a success with jets-shell interaction simulations that include more ingredients.

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Muhammad Akashi, Noam Soker. 2018-09-06. The formation of `columns crowns' by jets interacting with a circumstellar dense shell. https://doi.org/10.1093/mnras%2Fsty2479

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