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arXiv · 2102.08194

Comparison of cosmic string and superstring models to NANOGrav 12.5-year results

Jose J. Blanco-Pillado·Ken D. Olum·Jeremy M. Wachter
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Abstract

We compare the spectrum of the stochastic gravitational wave background produced in several models of cosmic strings with the common-spectrum process recently reported by NANOGrav. We discuss theoretical uncertainties in computing such a background, and show that despite such uncertainties, cosmic strings remain a good explanation for the potential signal, but the consequences for cosmic string parameters depend on the model. Superstrings could also explain the signal, but only in a restricted parameter space where their network behavior is effectively identical to that of ordinary cosmic strings.

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Jose J. Blanco-Pillado, Ken D. Olum, Jeremy M. Wachter. 2021-02-16. Comparison of cosmic string and superstring models to NANOGrav 12.5-year results. https://doi.org/10.1103/physrevd.103.103512

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