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

TL;DR

NewCluster is a high-resolution cosmological simulation of a galaxy cluster, featuring advanced resolution, detailed feedback, and chemical modeling, enabling in-depth studies of galaxy formation and evolution.

Contribution

It introduces a novel high-resolution cluster simulation with enhanced spatial, mass, and temporal resolution, and incorporates Monte Carlo tracers for improved gas dynamics analysis.

Findings

High stellar mass resolution of 2×10^4 M_sun for early galaxy assembly

Spatial resolution of 68 parsecs for detailed galaxy kinematics

Short snapshot interval of 15 Myr for tracking galaxy evolution

Abstract

We introduce NewCluster, a new high-resolution cluster simulation designed to serve as the massive halo counterpart of the modern cosmological galaxy evolution framework. The zoom-in simulation targets a volume of $4.1\sigma$ overdensity region, which is expected to evolve into a galaxy cluster with a virial mass of $5 \times 10^{14} M_\odot$, 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 found in its resolutions. Its stellar mass resolution of $2 \times 10^{4} M_\odot$ 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 powerful to study the detailed kinematic structure of galaxies. The time interval between snapshots is also exceptionally short-15 Myr-which is ideal for monitoring changes in the physical properties of galaxies, particularly during their orbital motion within a larger halo. The simulation has up-to-date feedback schemes for supernovae and active galactic nuclei. 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 employ Monte Carlo-based tracer particles in NewCluster, enabling a wide range of scientific investigations.