Population III star formation and feedback in ultra-faint dwarf galaxies

Investigate how alternative Population III star-formation and feedback scenarios influence the present-day properties of dwarf galaxies by developing and implementing a dedicated Population III subgrid model within the RIGEL framework.

Background

The simulations do not include dedicated physics for Population III stars, pair-instability supernovae, or Population III-specific metal yields. Instead, stars are formed across all metallicities using the same star-formation criteria and initial mass function, while Population III yields are obtained by extrapolating the Population II model. This omission may contribute to the relatively low metallicities predicted for the faintest dwarf galaxies.

The paper identifies the formation and evolution of Population III stars as highly uncertain and motivates future development of a RIGEL subgrid model combining analytical Population III star-formation prescriptions with Population III feedback models. The unresolved issue is how different Population III formation and feedback histories propagate into the observable properties of present-day dwarf galaxies.

References

The formation and evolution of Pop III stars are still highly uncertain (see \citealt{2023ARA&A..61...65K:Klessen} for a review). One of the goals of the RIGEL project is to develop a subgrid Pop III star formation model that combines the analytical framework of for Pop~III star formation with the Pop~III feedback prescription of , integrating both within RIGEL. With this new model, we aim in future work to investigate a variety of Pop III formation and feedback scenarios and to predict how they influence the present-day properties of dwarf galaxies.

— RIGEL: Ultra-faint dwarf galaxy diversity shaped by inhomogeneous cosmic reionization  (2609.09267 - Deng et al., 8 Sep 2026) in Section 6.1, “Caveats” (Section \ref{sec:cav})