Bipolar planetary nebulae from outflow collimation by common envelope evolution
ABSTRACT The morphology of bipolar planetary nebulae (PNe) can be attributed to interactions between a fast wind from the central engine and the dense toroidal-shaped ejecta left over from common envelope (CE) evolution. Here we use the 3D hydrodynamic adaptive mesh refinement (AMR) code AstroBEAR to study the possibility that bipolar PN outflows can emerge collimated even from an uncollimated spherical wind in the aftermath of a CE event. The output of a single CE simulation via the smoothed particle hydrodynamics (SPH) code phantom serves as the initial conditions. Four cases of winds, all with high enough momenta to account for observed high momenta pre-PN outflows, are injected spherically from the region of the CE binary remnant into the ejecta. We compare cases with two different momenta and cases with no radiative cooling versus application of optically thin emission via a cooling curve to the outflow. Our simulations show that in all cases highly collimated bipolar outflows result from deflection of the spherical wind via the interaction with the CE ejecta. Significant asymmetries between the top and bottom lobes are seen in all cases. The asymmetry is strongest for the lower momentum case with radiative cooling. While real post-CE winds more »
- Award ID(s):
- 1813298
- Publication Date:
- NSF-PAR ID:
- 10269423
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 497
- Issue:
- 3
- Page Range or eLocation-ID:
- 2855 to 2869
- ISSN:
- 0035-8711
- Sponsoring Org:
- National Science Foundation
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