Applicability and redshift evolution of the globular-cluster–halo-mass relation

Determine whether the empirical globular-cluster–halo-mass relation calibrated from nearby galaxies remains applicable at high redshift, particularly at redshifts around 2–3, and characterize any evolution in its normalization between redshift 3 and the present day.

Background

CosmoDyn determines the number of globular clusters from an empirical relation linking the total globular-cluster population to the virial mass of the host halo. That relation is calibrated using nearby galaxies, but the framework initializes globular-cluster populations at high redshift, including redshifts around 2–3.

The paper notes that the relation’s applicability at these epochs is unresolved and cites work suggesting that its normalization may evolve by as much as an order of magnitude between redshift 3 and redshift 0. CosmoDyn therefore introduces the user-defined scaling parameter ALPHA to explore different normalizations, but a physically established redshift-dependent calibration remains unavailable.

References

Since this relation is calibrated using nearby galaxies, its applicability at high redshift ($z\simeq2$--3) remains uncertain.

— CosmoDyn: a semi-analytic post-processing framework for the dynamical evolution of compact stellar systems and black holes in cosmological simulations  (2609.18821 - Boldrini et al., 16 Sep 2026) in Section 4.1, “Initial conditions for globular clusters”