3D hydrodynamical survey of the impact of a companion on the morphology and dynamics of AGB outflow

TL;DR

This study uses 3D hydrodynamic simulations to explore how a binary companion influences the shape and movement of AGB star outflows, revealing that a sufficiently massive companion can significantly alter wind velocities.

Contribution

It introduces a classification parameter to categorize wind structures caused by binary interactions in AGB outflows, highlighting the impact of companion mass on wind dynamics.

Findings

Companions can create complex, non-spherical wind morphologies.

A classification parameter effectively categorizes wind structures.

Massive companions influence wind velocity via the slingshot mechanism.

Abstract

With the use of high-resolution ALMA observations, complex structures that resemble those observed in post-AGB stars and planetary nebulae are detected in the circumstellar envelopes of low-mass evolved stars. These deviations from spherical symmetry are believed to be caused primarily by the interaction with a companion star or planet. With the use of three-dimensional hydrodynamic simulations, we study the impact of a binary companion on the wind morphology and dynamics of an AGB outflow. We classifiy the wind structures and morphology that form in these simulations with the use of a classification parameter, constructed with characteristic parameters of the binary configuration. Finally we conclude that the companion alters the wind expansion velocity through the slingshot mechanism, if it is massive enough.