Fate of stellar components under bimodal subhalo mass-loss

Determine how the stellar component evolves for satellite galaxies associated with the two distinct subhalo evolution channels—moderate mass-loss survivors versus extreme mass-loss systems—in cosmological simulations, and ascertain whether the embedded galaxy survives when its host subhalo undergoes extreme tidal mass loss.

Background

The paper highlights that subhaloes in cosmological simulations exhibit two broad evolutionary channels: a modest mass-loss population that typically survives, and an extreme mass-loss population that often becomes unresolved. While dark-matter stripping has been studied extensively, how the embedded stellar component behaves across these two channels is less well constrained.

Because stars form deep in the subhalo potential, their stripping may lag behind that of dark matter, raising the question of whether galaxies can survive when their host subhaloes suffer extreme mass loss. Clarifying the stellar response in both channels is necessary to understand the ultimate fates of satellites and to inform semi-analytic models.

References

Given this bimodal evolution of the subhalo population, a critical open question is what happens to the stellar component for each population. Do they follow the same evolution, and, do we expect the galaxy to survive when its subhalo experiences extreme mass loss?

— The tidal evolution of satellite galaxies in cosmological simulations: insights from COLIBRE  (2604.03105 - He et al., 3 Apr 2026) in Introduction

Given both numerical and theoretical limitations, it is unclear whether this non-standard mass-to-light ratio is physical or a numerical error, so these galaxies were excluded from our analysis.

— Inferring the Dark from the Observable: Estimating Halo Masses Using Galaxy Properties  (2608.19154 - Chen et al., 19 Aug 2026) in Section 2.1, “Sample Selection of Halos and Galaxies” (label: sec:method_data_subselect)