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Superconducting cosmic strings as sources of cosmological fast radio bursts

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 نشر من قبل Yi-Fu Cai
 تاريخ النشر 2017
  مجال البحث فيزياء
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In this paper we calculate the radio burst signals from three kinds of structures of superconducting cosmic strings. By taking into account the observational factors including scattering and relativistic effects, we derive the event rate of radio bursts as a function of redshift with the theoretical parameters $Gmu$ and $mathcal{I}$ of superconducting strings. Our analyses show that cusps and kinks may have noticeable contributions to the event rate and in most cases cusps would dominate the contribution, while the kink-kink collisions tend to have secondary effects. By fitting theoretical predictions with the normalized data of fast radio bursts, we for the first time constrain the parameter space of superconducting strings and report that the parameter space of $Gmu sim [10^{-14}, 10^{-12}]$ and $mathcal{I} sim [10^{-1}, 10^{2}] ~ rm{GeV}$ fit the observation well although the statistic significance is low due to the lack of observational data. Moreover, we derive two types of best fittings, with one being dominated by cusps with a redshift $z = 1.3$, and the other dominated by kinks at the range of the maximal event rate.

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