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arXiv · 2108.08220

The Global 21 cm Signal of a Network of Cosmic String Wakes

Oscar F. Hernández
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Abstract

In previous works we discussed the 21 cm signature of a single cosmic string wake. However the 21 cm brightness temperature is influenced by a network of cosmic string wakes, and not one single wake. In this work we consider the signal from a network of wakes laid down during the matter era. We also improve on the previous calculation of a single wake signature. Finally we calculate the enhancement of the global 21 cm brightness temperature due to a network of wakes and discuss its affects of the signal measured in the Wouthuysen-Field absorption trough. We estimated that for string tensions between $10^{-8}$ to $10^{-7}$ there would be between a 10% to a factor 2 enhancement in the signal.

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Oscar F. Hernández. 2021-08-18. The Global 21 cm Signal of a Network of Cosmic String Wakes. https://doi.org/10.1093/mnras%2Fstab2634

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