CosmoDyn: a semi-analytic post-processing framework for the dynamical evolution of compact stellar systems and black holes in cosmological simulations
Abstract
Although a large number of cosmological simulations are now publicly available, their spatial and mass resolutions remain insufficient to accurately follow the dynamics of compact stellar systems and black holes. A complementary approach is therefore required to exploit the cosmological assembly histories encoded in these simulations without rerunning them. We present CosmoDyn, an open-source Python framework that reconstructs time-dependent galactic environments from any cosmological simulations and explicitly follows unresolved compact objects within them. A distinctive feature of CosmoDyn is that it models not only the main host galaxy but also its accreted satellites via moving gravitational potentials. The framework can therefore account simultaneously for the delivery of ex-situ populations and for the dynamical influence of satellites on in-situ population already present in the host. The modular pipeline comprises four main stages: reconstructing the evolving host and satellite potentials; generating in-situ and ex-situ populations of compact objects; integrating their orbits with configurable prescriptions for dynamical friction, and mass loss; and modeling tidal streams. Once reconstructed, the same cosmological environment can be reused to explore different objects, initial conditions, and physical prescriptions at low computational cost. CosmoDyn thus enables rapid parameter exploration and applications to statistically significant galaxy samples, while its modular architecture is designed to incorporate progressively more realistic potentials, and formation models.
Related
- CROMA: a GPU-accelerated Fokker--Planck solver for modeling non-thermal emission in post-processing cosmological simulations
- OpenCosmo: Community Portal and Analysis Framework for Flagship Cosmological Simulations
- Rates of tidal disruption events from constrained cosmological simulations of the local Universe: population properties and implications for transient surveys
- Updated observational constraints on ϕCDM dynamical dark energy cosmological models
- Coupling between stellar and HI lopsidedness in Milky Way--type galaxies from the Auriga Superstars cosmological simulations
BibTeX
@misc{boldrini2026cosmodyn,
title = {{CosmoDyn: a semi-analytic post-processing framework for the dynamical evolution of compact stellar systems and black holes in cosmological simulations}},
author = {Pierre Boldrini and Paola Di Matteo and David Katz and Laia Casamiquela and Chervin Laporte and Maxime Assuerus and Marco Montuori and Glenn van de Ven},
howpublished = {HAL},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.18821},
eprint = {2609.18821},
archivePrefix = {arXiv},
url = {https://hal.science/hal-05774439v1},
}
RIS
TY - UNPB
TI - CosmoDyn: a semi-analytic post-processing framework for the dynamical evolution of compact stellar systems and black holes in cosmological simulations
AU - Pierre Boldrini
AU - Paola Di Matteo
AU - David Katz
AU - Laia Casamiquela
AU - Chervin Laporte
AU - Maxime Assuerus
AU - Marco Montuori
AU - Glenn van de Ven
PY - 2026
DA - 2026/09/16
PB - HAL
DO - 10.48550/arxiv.2609.18821
UR - https://hal.science/hal-05774439v1
AB - Although a large number of cosmological simulations are now publicly available, their spatial and mass resolutions remain insufficient to accurately follow the dynamics of compact stellar systems and black holes. A complementary approach is therefore required to exploit the cosmological assembly histories encoded in these simulations without rerunning them. We present CosmoDyn, an open-source Python framework that reconstructs time-dependent galactic environments from any cosmological simulations and explicitly follows unresolved compact objects within them. A distinctive feature of CosmoDyn is that it models not only the main host galaxy but also its accreted satellites via moving gravitational potentials. The framework can therefore account simultaneously for the delivery of ex-situ populations and for the dynamical influence of satellites on in-situ population already present in the host. The modular pipeline comprises four main stages: reconstructing the evolving host and satellite potentials; generating in-situ and ex-situ populations of compact objects; integrating their orbits with configurable prescriptions for dynamical friction, and mass loss; and modeling tidal streams. Once reconstructed, the same cosmological environment can be reused to explore different objects, initial conditions, and physical prescriptions at low computational cost. CosmoDyn thus enables rapid parameter exploration and applications to statistically significant galaxy samples, while its modular architecture is designed to incorporate progressively more realistic potentials, and formation models.
ER -