Model the survival of Gep I in the Andromeda XXV potential

Construct dynamical models to determine whether an extended, low-mass star cluster with Gep I’s present-day properties can survive in the inferred gravitational potential of Andromeda XXV, thereby constraining the galaxy’s dark matter distribution.

Background

The survival of extended star clusters in low-mass dwarf galaxies provides a possible probe of their central dark matter density profile. Existing simulations of the Eri II cluster generally struggle to reconcile its survival with a cuspy dark matter halo, whereas a central core offers a more natural explanation. The improved measurements of Gep I motivate analogous N-body studies for Andromeda XXV, whose dark matter profile remains substantially uncertain.

References

While substantial uncertainties in the inferred dark matter profile preclude definitive conclusions, the survival of a low-mass, extended star cluster deep in its potential well may bring further insight.

— The solitary star cluster of the Andromeda XXV dwarf spheroidal  (2608.26959 - Crociati et al., 27 Aug 2026) in Section 3.2, “Comparing the properties of the star clusters in And XXV and Eri II”; Summary and conclusions