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Constraints on the redshift of reionization from CMB data

Jens Schmalzing·Jesper Sommer-Larsen·Martin Goetz
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Abstract

We use the recent CMB power spectrum measurement by the Maxima experiment (Hanany et al. 2000) to constrain the redshift of reionization z_re. This becomes possible by combining the CMB data with cosmological parameters from various independent measurements, including Big Bang Nucleosynthesis (BBN) and X-ray cluster data. Most notably, our results provide a robust lower bound on z_re. We find that z_re>15 (8) at the 68% (95%) confidence level, unless the Hubble constant is larger than 75 km/s/Mpc.

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Jens Schmalzing, Jesper Sommer-Larsen, Martin Goetz. 2000-10-03. Constraints on the redshift of reionization from CMB data. https://arxiv.org/abs/astro-ph/0010063

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