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Recognizing the First Radiation Sources Through Their 21-cm Signature

Leonid Chuzhoy·Marcelo A. Alvarez·Paul R. Shapiro
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Abstract

At the beginning of the reionization epoch, radiation sources produce fluctuations in the redshifted 21-cm background. We show that different types of sources (such as miniquasars, Pop II and III stars, supernovae, etc.) produce distinct signatures in the 21-cm signal radial profiles and statistical fluctuations, through which they can be identified. Further, we show that the 21-cm signal from X-ray emitting sources is much easier to observe than was expected, due to a previously neglected pumping mechanism.

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Leonid Chuzhoy, Marcelo A. Alvarez, Paul R. Shapiro. 2006-08-11. Recognizing the First Radiation Sources Through Their 21-cm Signature. https://doi.org/10.1086/507626

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