Superconducting cosmic string loops as sources for fast radio bursts

Abstract

The cusp burst radiation of superconducting cosmic string (SCS) loops is thought to be a possible origin of observed fast radio bursts with the model-predicted radiation spectrum and the redshift- and energy-dependent event rate, we fit the observational redshift and energy distributions of 21 Parkes fast radio bursts and constrain the model parameters. It is found that the model can basically be consistent with the observations, if the current on the SCS loops has a present value of $\ensuremath{\sim}{10}^{16}{\ensuremath{\mu}}_{17}^{9/10}\text{ }\text{ }\mathrm{esu}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ and evolves with redshift as an empirical power law $\ensuremath{\sim}(1+z{)}^{\ensuremath{-}1.3}$, where ${\ensuremath{\mu}}_{17}=\ensuremath{\mu}/{10}^{17}\text{ }\text{ }\mathrm{g}\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$ is the string tension. This current evolution may provide a clue to probe the evolution of the cosmic magnetic fields and the gathering of the SCS loops to galaxy clusters.