# A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in omega Centauri

## TL;DR

This study analyzes the chemical composition of star ROA 276 in omega Centauri, providing evidence that fast-rotating low-metallicity massive stars contributed to early Universe heavy element production.

## Contribution

It presents the first detailed chemical signature linking a specific star to nucleosynthesis in fast-rotating massive stars at low metallicity.

## Key findings

- ROA 276 has an unusually high [Sr/Ba] ratio.
- The star's abundance pattern matches models of 20 Msun fast-rotating stars.
- No other nucleosynthetic source explains the neutron-capture elements.

## Abstract

We present a chemical abundance analysis of a metal-poor star, ROA 276, in the stellar system omega Centauri. We confirm that this star has an unusually high [Sr/Ba] abundance ratio. Additionally, ROA 276 exhibits remarkably high abundance ratios, [X/Fe], for all elements from Cu to Mo along with normal abundance ratios for the elements from Ba to Pb. The chemical abundance pattern of ROA 276, relative to a primordial omega Cen star ROA 46, is best fit by a fast-rotating low-metallicity massive stellar model of 20 Msun, [Fe/H] = -1.8, and an initial rotation 0.4 times the critical value; no other nucleosynthetic source can match the neutron-capture element distribution. ROA 276 arguably offers the most definitive proof to date that fast-rotating massive stars contributed to the production of heavy elements in the early Universe.