Stellar yields from metal-rich asymptotic giant branch models

TL;DR

This paper provides new theoretical stellar yields and surface abundances for metal-rich asymptotic giant branch (AGB) models, covering a range of initial masses and metallicities, including the first s-process yields for super-solar metallicity stars.

Contribution

It introduces comprehensive AGB stellar yields and surface abundances for multiple metallicities and masses, including novel s-process yields for high-metallicity stars.

Findings

First s-process yields for Z=0.03 AGB stars.

Complete yields for models >6 M_sun at all metallicities.

Surface abundance ratios useful for observational comparisons.

Abstract

We present new theoretical stellar yields and surface abundances for three grids of metal-rich asymptotic giant branch (AGB) models. Post-processing nucleosynthesis results are presented for stellar models with initial masses between 1$M_{\odot}$ and 7.5$M_{\odot}$ for $Z=0.007$, and 1$M_{\odot}$ and 8$M_{\odot}$ for $Z=0.014$ (solar) and $Z=0.03$. We include stellar surface abundances as a function of thermal pulse on the AGB for elements from C to Bi and for a selection of isotopic ratios for elements up to Fe and Ni (e.g., $^{12}$C/$^{13}$C), which can be obtained from observations of molecules in stars and from the laboratory analysis of meteoritic stardust grains. Ratios of elemental abundances of He/H, C/O, and N/O are also included, which are useful for direct comparison to observations of AGB stars and their progeny including planetary nebulae. The integrated elemental stellar yields are presented for each model in the grid for hydrogen, helium and all stable elements from C to Bi. Yields of Li are also included for intermediate-mass models with hot bottom burning. We present the first $slow$ neutron-capture ($s$-process) yields for super-solar metallicity AGB stars with $Z=0.03$, and the first complete $s$-process yields for models more massive than 6$M_{\odot}$ at all three metallicities.