The First Stars

TL;DR

Pop III stars are crucial for understanding early universe phenomena, but their properties remain largely unknown due to observational and modeling challenges; future supernova detection and chemical analysis offer promising constraints.

Contribution

This paper reviews current simulation challenges and discusses observational strategies to constrain the properties of the first stars.

Findings

Numerical models cannot yet predict Pop III star masses.

Detection of Pop III supernovae can help constrain their properties.

Chemical abundances in ancient stars may reveal Pop III nucleosynthesis.

Abstract

Pop III stars are the key to the character of primeval galaxies, the first heavy elements, the onset of cosmological reionization, and the seeds of supermassive black holes. Unfortunately, in spite of their increasing sophistication, numerical models of Pop III star formation cannot yet predict the masses of the first stars. Because they lie at the edge of the observable universe, individual Pop III stars will also remain beyond the reach of telescopes for the foreseeable future, and so their properties remain unknown. However, it will soon be possible to constrain their masses by the direct detection of their supernovae and by reconciling their nucleosynthetic yields to the chemical abundances measured in ancient metal-poor stars in the Galactic halo, some of which may be bear the ashes of the first stars. Here, I review current problems on the simulation frontier in Pop III star formation and discuss the best prospects for constraining their properties observationally in the near term.