Introducing the THESAN project: radiation-magnetohydrodynamic simulations of the epoch of reionization

Understand

We introduce the THESAN project, a suite of large volume (L = 95.5 cMpc) radiation-magnetohydrodynamic simulations that simultaneously model the large-scale statistical properties of the IGM during reionization and the resolved characteristics of the galaxies responsible for it.

• The flagship simulation has dark matter (DM) and baryonic mass resolutions of $3.1 \times 10^6$ $M_\odot$ and $5.8 \times 10^5 $ $M_\odot$, respectively.
• The gravitational forces are softened on scales of 2.2 ckpc with the smallest cell sizes reaching 10 pc at z=5.5, enabling predictions down to the atomic cooling limit.
• The simulations use an efficient radiation hydrodynamics solver (AREPO-RT) that precisely captures the interaction between ionizing photons and gas, coupled to well-tested galaxy formation (IllustrisTNG) and dust models to accurately predict the properties of galaxies.