Astrophysics and Cosmology from the Epoch of reionisation and the cosmic dawn with the Square Kilometre Array.

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Currently Cosmological information can be obtained via the distribution of Hydrogen atoms in the Universe in two main ways. Firstly Quasars from the Hubble deep field are used to probe the Universe for the amount of Hydrogen via the Lyman Alpha Forest in any one direction up to about a redshift of z=6. Secondly the Cosmic Microwave Background (CMB) provides information of density fluctuations of the Universe around the time of recombination of Hydrogen atoms after the Big Bang, at a redshift of about z=1100. However the range in between these two techniques is not nearly as well known experimentally. The Square Kilometre Array (SKA) intends to shed light on the period of redshifts z=6 to z=27 by analysing fluctuations in the 21cm hyperfine emission line of neutral Hydrogen with a new generation of radio interferometers. Analysis of the powers spectrum should produce a model of the evolution of neutral Hydrogen atoms, as density perturbations shown in the CMB grow into Galaxies, until the majority of the Hydrogen in the Universe is re-ionised. This project is aimed towards looking at Bayesian statistical analyses used on theoretical data that will be similar to the real data produced by SKA when it is finished being built in Australia in 2020 (and also the data from HERA, a similar experiment under construction in South Africa). This semi-numerical simulation will hopefully allow us to understand the observations made by SKA in an astrophysical context, in terms of Galaxy formation during the Cosmic Dawn.