A Tale of Two Stars: Interferometric Studies of Post-AGB Binaries

TL;DR

This paper presents interferometric observations and modeling of two post-AGB binary systems with circumbinary disks, highlighting the importance of high-resolution data and radiative transfer models in understanding their evolution.

Contribution

It compares modeling results of two post-AGB binaries, assessing the applicability of protoplanetary disk models to evolved star systems.

Findings

Interferometric data reveal detailed disk structures.

Models show both successes and limitations in explaining observations.

High-angular-resolution observations are crucial for understanding post-AGB binaries.

Abstract

Binaries with circumbinary disks are commonly found among optically bright post-AGB stars. Although clearly linked to binary interaction processes, the formation, evolution and fate of these disks are still badly understood. Due to their compactness, interferometric techniques are required to resolve them. Here, we discuss our high-quality multiwavelength interferometric data of two prototypical yet very different post-AGB binaries, AC and 89 Herculis, as well as the modeling thereof with radiative transfer models. A detailed account of the data and models of both objects is published in three separate papers elsewhere; here we focus on comparing the modeling results for the two objects. In particular we discuss the successes and limitations of the models which were developed for protoplanetary disks around young stars. We conclude that multiwavelength high-angular-resolution observations and radiative transfer disk models are indispensible to understand these complex interacting objects and their place in the grand scheme of the (binary) evolution of low and intermediate mass stars.