Introducing NewCluster: First half of the history of a high-resolution cluster simulation

¹ Institut d’Astrophysique de Paris, Sorbonne Université, CNRS, UMR 7095 98 bis bd Arago 75014 Paris, France
² Department of Astronomy and Yonsei University Observatory, Yonsei University Seoul 03722, Republic of Korea
³ Korea Astronomy and Space Science Institute, 776, Daedeokdae-ro Yuseong-gu Daejeon 34055, Republic of Korea
⁴ Korea Institute of Advanced Studies (KIAS), 85 Hoegiro Dongdaemun-gu Seoul 02455, Republic of Korea
⁵ Kyung Hee University, Dept. of Astronomy & Space Science Yongin-shi Gyeonggi-do 17104, Republic of Korea

^★ Corresponding authors: This email address is being protected from spambots. You need JavaScript enabled to view it. ; This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 7 July 2025
Accepted: 17 November 2025

Abstract

Aims. We introduce NEWCLUSTER, a novel high-resolution cluster simulation designed to serve as the massive halo counterpart of the modern cosmological galaxy evolution framework.

Methods. The zoom-in simulation targets a volume of 4.1σ overdensity region, which is expected to evolve into a galaxy cluster with a virial mass of 5 × 10¹⁴ M_⊙, comparable to that of the Virgo Cluster. The zoom-in volume extends out to 3.5 virial radii from the central halo. The novelties of NEWCLUSTER are exemplified by its resolution. Its stellar mass resolution of 2 × 10⁴ M_⊙ is effective for tracing the early assembly of massive galaxies as well as the formation of dwarf galaxies. The spatial resolution of 68 parsecs in the best-resolved regions in the adaptive-mesh-refinement approach is a powerful tool for studying the detailed kinematic structure of galaxies. The time interval between snapshots is also exceptionally short (i.e., 15 Myr). This is ideal for monitoring changes in the physical properties of galaxies, particularly during their orbital motion within a larger halo. The simulation includes up-to-date feedback schemes for supernovae (SNe) and active galactic nuclei (AGNs). The chemical evolution is calculated for ten elements, along with dust calculation that includes the formation, size change, and destruction. To overcome the limitations of the Eulerian approach used for gas dynamics in this study, we employed Monte Carlo-based tracer particles in NEWCLUSTER, enabling a wide range of scientific investigations.

Results. The simulation has passed z = 0.8, covering well over half of its cosmic history. We released the early data with the expectation they will facilitate studies of the early evolution of galaxies and overdensities.