Common Envelope Shaping of Planetary Nebulae. IV. From Proto-planetary to Planetary Nebula

TL;DR

This study uses 2D hydrodynamical simulations to explore how binary interactions and stellar winds shape the evolution of proto-planetary nebulae into planetary nebulae, revealing mass-dependent fragmentation and morphological outcomes.

Contribution

It provides new insights into the effects of magnetic fields, photoionization, and stellar mass on nebula shaping during the transition phase, using detailed simulations of binary systems post-common envelope.

Findings

Bipolar proto-planetary nebulae evolve into bipolar planetary nebulae.

Fragmentation patterns depend on stellar mass, leading to different structures.

Magnetic fields often dissipate, leaving behind collimated features.

Abstract

We present 2D hydrodynamical simulations of the transition of a proto-planetary nebula to a planetary nebula for central stars in binary systems that have undergone a common envelope event. After 1,000 yr of magnetically driven dynamics (proto-planetary nebula phase), a line-driven stellar wind is introduced into the computational domain and the expansion of the nebula is simulated for another 10,000 yr, including the effects of stellar photoionization. In this study we consider central stars with main sequence (final) masses of 1 (0.569) and 2.5 (0.677) \Mo, together with a 0.6 \Mo ma in sequence companion. Extremely bipolar, narrow-waisted proto-planetary nebulae result in bipolar planetary nebulae, while the rest of the shapes mainly evolve into elliptical planetary nebulae. The initial magnetic field's effects on the collimated structures, such as jets, tend to disappear in most of the cases, leaving behind the remnants of those features in only a few cases. Equatorial zones fragmented mainly by photoionization ( 1 \Mo progenitors), result in ``necklace'' structures made of cometary clumps aligned with the radiation field. On the other hand, fragmentation by photoionization and shocked wind ( 2.5 \Mo progenitors) give rise to the formation of multiple clumps in the latitudinal direction, which remain within the lobes, close to the center, which are immersed and surrounded by hot shocked gas, not necessarily aligned with the radiation field. These results reveal that the fragmentation process has a dependence on the stellar mass progenitor. This fragmentation is made possible by the distribution of gas in the previous post-common envelope proto-planetary nebula as sculpted by the action of the jets.