Cosmic Superstrings Revisited in Light of NANOGrav 15-Year Data

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.