A near field cosmology study of heavy elements in very metal-poor stars

TL;DR

This study analyzes heavy element abundances in very metal-poor stars to understand early Galactic evolution and neutron-capture element formation sites through high-resolution stellar observations.

Contribution

It provides a detailed abundance analysis of neutron-capture elements in metal-poor stars, linking observations to supernova yields and early stellar populations.

Findings

Heavy element abundances trace supernova type II yields.

Neutron-capture elements at low metallicity originate from early supernovae.

Results inform models of early Galactic chemical evolution.

Abstract

Studying a range of old metal-poor stars provides information over cosmological timescales of our Galaxy. Such studies are indicative of the pristine gases and evolution of the Milky Way. Deriving stellar parameters and abundances from high-resolution observations of stars at various stellar evolution stages (including old dwarfs and RR Lyrae), allows us to use these abundances as tracers of an even earlier progenitor population. Here, we carry out a detailed abundance study of mainly heavy elements (Z > 38), i.e. neutron-capture elements, which we at low metallicities ([Fe/H] < -2.5) take as pure supernova type II products. A comparison of the derived abundances to type II supernova yields of heavy elements provides knowledge of the old stellar generations as well as properties of neutron-capture formation sites.