Analysis of the Principle and Simulations for Re-ionization of THESAN

The re-ionization era was always mysterious to humans, because of its great time distance. It is the period when galaxies form due to dark matter congregating and emit high energy photons ionizing the surrounding (entire) universe. The THESAN simulation is a successful program that uses computers and models that simulates what happened in the re-ionization era. However, this is a complex program that contains multiple research directions, the aim of this paper is to summarize the work of the THESAN team giving first a background information about simulations, the re-ionization era, and certain models for re-ionization era. Then, this study introduces the THESAN model which contains three important parts of radiation, galaxy formation, and cosmic dust. Afterwards the results of the simulation such as Lyman alpha emission will be summarized and observation methods such as 21 cm line will be illustrated. At last, there will be discussion of the limitations of the THESAN study and its future outlooks majorly focusing on the use of JWST detection abilities on the THESAN simulation.