Binary Central Stars of Planetary Nebulae Discovered Through Photometric Variability III: The Central Star of Abell 65

TL;DR

This paper presents detailed photometric observations of the central star of Abell 65, confirming its close binary nature and refining its orbital period, contributing to understanding binary evolution in planetary nebulae.

Contribution

It provides long-term, multi-wavelength photometry and analysis that refines the orbital period and binary parameters of Abell 65, enhancing knowledge of binary-central star systems.

Findings

Confirmed close binary companion of Abell 65

Refined orbital period to 1.0037577 days

Identified discrepancies with previous model parameters

Abstract

A growing number of close binary stars are being discovered among central stars of planetary nebulae. Recent and ongoing surveys are finding new systems and contributing to our knowledge of the evolution of close binary systems. The push to find more systems was largely based on early discoveries which suggested that 10 to 15% of all central stars are close binaries. One goal of this series of papers is confirmation and classification of these systems as close binaries and determination of binary system parameters. Here we provide time-resolved multi-wavelength photometry of the central star of Abell 65 as well as further analysis of the nebula and discussion of possible binary--nebula connections. Our results for Abell 65 confirm recent work showing that it has a close, cool binary companion, though several of our model parameters disagree with the recently published values. With our longer time baseline of photometric observations from 1989--2009 we also provide a more precise orbital period of 1.0037577 days.