Cosmic Superstrings Revisited in Light of NANOGrav 15-Year Data

John Ellis; Marek Lewicki; Chunshan Lin; Ville Vaskonen

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arXiv · 2306.17147

Cosmic Superstrings Revisited in Light of NANOGrav 15-Year Data

John Ellis·Marek Lewicki·Chunshan Lin·Ville Vaskonen

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Abstract

We analyze cosmic superstring models in light of NANOGrav 15-year pulsar timing data. A good fit is found for a string tension $G \mu \sim 10^{-12} - 10^{-11}$ and a string intercommutation probability $p \sim 10^{-3} - 10^{-1}$. Extrapolation to higher frequencies assuming standard Big Bang cosmology is compatible at the 68\% CL with the current LIGO/Virgo/KAGRA upper limit on a stochastic gravitational wave background in the 10 to 100 Hz range. The superstring interpretation of the NANOGrav data would be robustly testable by future experiments even in modified cosmological scenarios.

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John Ellis, Marek Lewicki, Chunshan Lin, Ville Vaskonen. 2023-06-29. Cosmic Superstrings Revisited in Light of NANOGrav 15-Year Data. https://arxiv.org/abs/2306.17147

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