A barium-rich binary central star in Abell 70

TL;DR

This paper reports the discovery of a binary central star in Abell 70, featuring a barium star secondary and a hot white dwarf, providing a unique case for studying nucleosynthesis.

Contribution

It identifies a barium-rich binary central star in Abell 70, linking stellar chemistry with planetary nebula properties for the first time.

Findings

Central star is a binary with a barium star secondary.

Nebula exhibits Type-I chemical abundances with helium and nitrogen enrichment.

Potential for future abundance studies to understand s-process nucleosynthesis.

Abstract

We have found the central star of Abell 70 (PN G038.1-25.4, hereafter A 70) to be a binary consisting of a G8 IV-V secondary and a hot white dwarf. The secondary shows enhanced Ba II and Sr II features, firmly classifying it as a barium star. The nebula is found to have Type-I chemical abundances with helium and nitrogen enrichment, which combined with future abundance studies of the central star, will establish A 70 as a unique laboratory for studying s-process AGB nucleosynthesis.