Contribution of combined stellar channels to UV-upturn evolution

Determine whether the combined contribution of canonical evolved UV-emitting channels and low-mass stars formed from hypernova-enriched gas contributes measurably to the redshift evolution of the ultraviolet upturn.

Background

The paper proposes a speculative connection between the observed UV-excess FGK stars, hypernova-enriched stellar populations, and the redshift evolution of the UV upturn in galaxies. The authors suggest that populations formed near the peak of cosmic star formation could contain both low-mass stars born from energetically enriched gas and coeval UV-bright post-main-sequence stars.

This proposed combination is not established by the stellar sample. The authors state that population-synthesis models must jointly follow canonical evolved channels, the formation of low-mass stars from hypernova-enriched gas, and their later UV evolution in order to test whether the combination affects the observed redshift dependence of the UV upturn.

References

Establishing whether this combination contributes measurably to the redshift evolution of the UV upturn will require population-synthesis models that jointly follow the canonical evolved channels and the formation and subsequent UV evolution of low-mass stars born from hypernova-enriched gas.

— The T-GEX project. II. Chrono-chemo-dynamic signatures of UV-bright FGK stars  (2609.19257 - Beltrán et al., 16 Sep 2026) in Section 3.4, Implications for unresolved UV-upturn-related stellar populations