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arXiv · 1306.2354

Complete history of the observable 21-cm signal from the first stars during the pre-reionization era

Anastasia Fialkov·Rennan Barkana·Arazi Pinhas·Eli Visbal
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Abstract

We present the first complete calculation of the history of the inhomogeneous 21-cm signal from neutral hydrogen during the era of the first stars. We use hybrid computational methods to capture the large-scale distribution of the first stars, whose radiation couples to the neutral hydrogen emission, and to evaluate the 21-cm signal from z ~ 15-35. In our realistic picture large-scale fluctuations in the 21-cm signal are sourced by the inhomogeneous density field and by the Ly-alpha and X-ray radiative backgrounds. The star formation is suppressed by two spatially varying effects: negative feedback provided by the Lyman-Werner radiative background, and supersonic relative velocities between the gas and dark matter. Our conclusions are quite promising: we find that the fluctuations imprinted by the inhomogeneous Ly-alpha background in the 21-cm signal at z ~ 25 should be detectable with the Square Kilometer Array.

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Anastasia Fialkov, Rennan Barkana, Arazi Pinhas, Eli Visbal. 2013-06-10. Complete history of the observable 21-cm signal from the first stars during the pre-reionization era. https://doi.org/10.1093/mnrasl%2Fslt135

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