Cosmic superstrings revisited in light of NANOGrav 15-year data
John Ellis, Marek Lewicki, Chunshan Lin, Ville Vaskonen
Abstract
We analyze cosmic superstring models in light of NANOGrav 15-year pulsar timing data. A good fit is found for a string tension $G\ensuremath{\mu}\ensuremath{\sim}{10}^{\ensuremath{-}12}--{10}^{\ensuremath{-}11}$ and a string intercommutation probability $p\ensuremath{\sim}{10}^{\ensuremath{-}3}--{10}^{\ensuremath{-}1}$. 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.
Topics & Concepts
PhysicsSuperstring theoryCosmic stringLIGOString (physics)Gravitational waveExtrapolationCosmologyPulsarGravitational wave backgroundAstrophysicsParticle physicsTheoretical physicsSupersymmetryStatisticsMathematicsCosmology and Gravitation TheoriesBlack Holes and Theoretical PhysicsPulsars and Gravitational Waves Research