Nucleosynthesis and chemical evolution of intermediate-mass stars: results from planetary nebulae

TL;DR

This paper analyzes planetary nebulae to study the nucleosynthesis and chemical evolution of intermediate-mass stars, providing detailed abundance data and correlations that test recent stellar evolution models.

Contribution

It offers a large, accurate dataset of chemical abundances in planetary nebulae across various galactic populations, enhancing understanding of stellar nucleosynthesis.

Findings

Determined average abundances of key elements in planetary nebulae.

Identified correlations between element abundances and stellar evolution.

Compared observed abundances with theoretical models.

Abstract

Planetary nebulae (PN) are an excellent laboratory to investigate the nucleosynthesis and chemical evolution of intermediate mass stars. In these objects accurate abundances can be obtained for several chemical elements that are manufactured or contaminated by the PN progenitor stars, such as He, N, C, and also elements that were originally produced by more massive stars of previous generations, namely O, Ne, Ar, and S. Some of these elements are difficult to study in stars, so that PN can be used in order to complement results obtained from stellar data. In the past few years, we have obtained a large sample of PN with accurately derived abundances, including objects of different populations, namely the solar neighbourhood, the galactic disk and anticentre, the galactic bulge and the Magellanic Clouds. In this work, we present the results of our recent analysis of the chemical abundances of He, O, N, S, Ar and Ne in galactic and Magellanic Cloud PN. Average abundances and abundance distributions of all elements are determined, as well as distance-independent correlations. These correlations are particularly important, as they can be directly compared with the predictions of recent theoretical evolutionary models for intermediate mass stars.