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arXiv · 0806.0372

A Flat Photoionization Rate at 2<z<4.2: Evidence for a Stellar-Dominated UV Background and Against a Decline of Cosmic Star Formation Beyond z~3

C. -A. Faucher-Giguere·A. Lidz·L. Hernquist·M. Zaldarriaga
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Abstract

We investigate the implications of our measurement of the Lyman-alpha forest opacity at redshifts 2 ~3. Our measurement argues against a star formation rate density declining beyond z~3, in contrast with existing state-of-the-art determinations of the cosmic star formation history from direct galaxy counts. Stellar emission from galaxies therefore likely reionized the Universe.

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C. -A. Faucher-Giguere, A. Lidz, L. Hernquist, M. Zaldarriaga. 2008-06-02. A Flat Photoionization Rate at 2<z<4.2: Evidence for a Stellar-Dominated UV Background and Against a Decline of Cosmic Star Formation Beyond z~3. https://doi.org/10.1086/590409

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