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Shaping Planetary Nebulae and Related Objects

Noam Soker
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Abstract

I review some open questions and other aspects concerning the shaping of planetary nebulae (PNs) and related objects. I attribute the non-spherical structures of PNs to binary companions, stellar or substellar. I emphasize the role of jets (or collimated fast wind: CFW) blown by an accreting stellar companion in shaping PNs and some related objects, and discuss the limited role of magnetic fields. I speculate that some stars which are leaving the asymptotic giant branch, i.e., becoming hotter, possess long-term (10-1000 years) oscillations; these may be related to semi-periodic concentric rings. I end with a list of objects whose shaping is related to the shaping processes of PNs, from young stellar objects to clusters of galaxies.

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Noam Soker. 2003-12-03. Shaping Planetary Nebulae and Related Objects. https://arxiv.org/abs/astro-ph/0309228

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