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Detections of the cross correlation signal between the 21cm signal during reionization and high-redshift Lyman Alpha emitters (LAEs) are subject to observational uncertainties which mainly include systematics associated with radio interferometers and LAE selection. These uncertainties can be reduced by increasing the survey volume and/or the survey luminosity limit, i.e. the faintest detectable Lyman Alpha (Ly$alpha$) luminosity. We use our model of high-redshift LAEs and the underlying reionization state to compute the uncertainties of the 21cm-LAE cross correlation function at $zsimeq6.6$ for observations with SKA1-Low and LAE surveys with $Delta z=0.1$ for three different values of the average IGM ionization state ($langlechi_mathrm{HI}rangle$=0.1, 0.25, 0.5). At $zsimeq6.6$, we find SILVERRUSH type surveys, with a field of view of 21 deg$^2$ and survey luminosity limits of $L_alphageq7.9times10^{42}$erg~s$^{-1}$, to be optimal to distinguish between an inter-galactic medium (IGM) that is 50%, 25% and 10% neutral, while surveys with smaller fields of view and lower survey luminosity limits, such as the 5 and 10 deg$^2$ surveys with WFIRST, can only discriminate between a 50% and 10% neutral IGM.
Upcoming 21cm surveys with the SKA1-LOW telescope will enable imaging of the neutral hydrogen distribution on cosmological scales in the early Universe. These surveys are expected to generate huge imaging datasets that will encode more information th
We study the signatures of reionization and ionizing properties of the early galaxies in the cross-correlations between the 21cm emission from the spin-flip transition of neutral hydrogen (HI) and the underlying galaxy population, in particular a sub
The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address
We review how the Square Kilometre Array (SKA) will address fundamental questions in cosmology, focussing on its use for neutral Hydrogen (HI) surveys. A key enabler of its unique capabilities will be large (but smart) receptors in the form of apertu
In order to precisely measure the cosmological parameters and answer the fundamental questions in cosmology, it is necessary to develop new, powerful cosmological probes, in addition to the proposed next-generation optical survey projects. The neutra