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Comparison of cosmic string and superstring models to NANOGrav 12.5-year results

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 نشر من قبل Jeremy Wachter
 تاريخ النشر 2021
  مجال البحث فيزياء
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We compare the spectrum of the stochastic gravitational wave background produced in several models of cosmic strings with the common-spectrum process recently reported by NANOGrav. We discuss theoretical uncertainties in computing such a background, and show that despite such uncertainties, cosmic strings remain a good explanation for the potential signal, but the consequences for cosmic string parameters depend on the model. Superstrings could also explain the signal, but only in a restricted parameter space where their network behavior is effectively identical to that of ordinary cosmic strings.



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