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arXiv · 1305.5541

Measuring the X-ray Background in the Reionization Era with First Generation 21 cm Experiments

Pierre Christian·Abraham Loeb
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Abstract

The X-ray background during the epoch of reionization is currently poorly constrained. We demonstrate that it is possible to use first generation 21 cm experiments to calibrate it. Using the semi-numerical simulation, 21cmFAST, we calculate the dependence of the 21 cm power spectrum on the X-ray background flux. Comparing the signal to the sensitivity of the Murchison Widefield Array (MWA) we find that in the redshift interval z=8-14 the 21 cm signal is detectable based on the upper limit set by the present-day unresolved soft X-ray background. We show that there is no degeneracy between the X-ray production efficiency and the Lyman-Alpha production efficiency and that the degeneracy with the ionization fraction of the intergalactic medium can be broken.

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Pierre Christian, Abraham Loeb. 2013-08-22. Measuring the X-ray Background in the Reionization Era with First Generation 21 cm Experiments. https://doi.org/10.1088/1475-7516%2F2013%2F09%2F014

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