Catalogue of central stars of extragalactic planetary nebulae

TL;DR

This paper compiles the largest catalogue of extragalactic central stars of planetary nebulae, enabling comparative studies of their properties across different galaxies and metallicities, thus advancing understanding of stellar evolution.

Contribution

It provides the most comprehensive and up-to-date catalogue of extragalactic CSPNe, including over 800 objects with detailed physical parameters from multiple galaxies.

Findings

First global comparison of CSPNe properties beyond the Milky Way.

Updated Hertzsprung-Russell diagrams reveal trends and outliers.

Resource for future spectroscopic studies and stellar evolution research.

Abstract

Context. Central stars of planetary nebulae (CSPNe) are essential for understanding the final evolutionary stages of low- and intermediate-mass stars. However, their study in extragalactic environments remains challenging due to their intrinsic faintness and the limited availability of high-quality data. Aims. We aim to provide a comprehensive and up-to-date catalogue of extragalactic CSPNe in order to enable a more complete view of their physical properties across different galactic environments and metallicities. Methods. The catalogue was assembled using data from the most recent and reliable literature sources. Priority was given to collecting effective temperatures and luminosities that have either been directly reported or consistently derived. When available, spectral types or specific spectral features -- such as P-Cygni profiles or broad H${\alpha}$ emission lines -- were also included. This approach allowed for broader characterisation of the sample, even when accurate classifications are not available. Results. We present a new compilation of extragalactic CSPNe -- the largest to date -- comprising over 800 objects located in the Magellanic Clouds, NGC 300, NGC 5128, and fifteen other nearby galaxies. This catalogue enables, for the first time, a global comparison of CSPNe physical parameters beyond the Milky Way. Updated Hertzsprung-Russell diagrams are provided featuring CSPNe from seven different galaxies, revealing trends and outliers that merit further investigation. The catalogue represents a valuable resource for future spectroscopic follow-up and for improving our understanding of post-AGB evolution in diverse galactic contexts.