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Early reionization by cosmic strings revisited

Levon Pogosian·Alexander Vilenkin
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Abstract

Measurements of the CMB temperature anisotropy and the temperature-polarization cross correlation by WMAP suggest a reionization redshift of $z \sim 17 \pm 5$. On the other hand, observations of high redshift galaxies indicate a presence of a significant fraction of neutral hydrogen at redshift $z\sim 6-7$. We show that cosmic strings with tensions well within, but not far from, current observation bounds could cause early star formation at a level sufficient to explain the high reionization redshift.

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Levon Pogosian, Alexander Vilenkin. 2004-09-24. Early reionization by cosmic strings revisited. https://doi.org/10.1103/physrevd.70.063523

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