The discovery and characterisation of binary central stars in planetary nebulae

TL;DR

This paper reports the discovery of over 10 new binary central stars in planetary nebulae, using targeted selection and novel observation methods, advancing understanding of the common-envelope phase in stellar evolution.

Contribution

It introduces new binary central star discoveries and discusses innovative observational strategies to identify and characterize these systems.

Findings

Over 10 new binary central stars discovered in recent years

Targeted morphological selection improves binary detection

Enhanced understanding of the common-envelope phase

Abstract

Close binary central stars of planetary nebulae are key in constraining the poorly-understood common-envelope phase of evolution, which in turn is critical in understanding the formation of a wide-range of astrophysical phenomena (including cataclysmic variables, low-mass X-ray binaries and supernovae type Ia). Here, I present the results of our on-going, targeted search for close-binaries in planetary nebulae which has led to the discovery of more than 10 new central binaries in just the last few years (almost the same as the total discovered during the 1980s and 1990s together). This success has been rooted in the targeted selection of objects for study, based on morphological features deemed typical of binarity, as well as novel observing strategies (including the employment of narrow-band filters for photometry to minimise nebular contamination), both of which are discussed. These new discoveries, coupled with the painstaking characterisation of both newly discovered systems and those from the literature, mean that we are now in a position to begin to probe the physics of the common-envelope phase.