Inhomogeneous Reionization Models in Cosmological Hydrodynamical Simulations

Understand

In this work we present a new hybrid method to simulate the thermal effects of the reionization in cosmological hydrodynamical simulations.

• The method improves upon the standard approach used in simulations of the intergalactic medium (IGM) and galaxy formation without a significant increase of the computational cost allowing for efficient exploration of the parameter space.
• The method uses a small set of phenomenological input parameters and combines a semi-numerical reionization model to solve for the topology of reionization and an approximate model of how reionization heats the IGM, with the massively parallel \texttt{Nyx} hydrodynamics code, specifically designed to solve for the structure of diffuse IGM gas.
• We have produced several large-scale high resolution cosmological hydrodynamical simulations ($2048^3$, $L_{\rm box} = 40$ Mpc/h) with different instantaneous and inhomogeneous HI reionization models that use this new methodology.