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Fibre Inflation and Reheating

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 نشر من قبل Paolo Cabella
 تاريخ النشر 2017
  مجال البحث فيزياء
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We present constraints on the reheating era within the string Fibre Inflation scenario, in terms of the effective equation-of-state parameter of the reheating fluid, $w_{reh}$. The results of the analysis, completely independent on the details of the inflaton physics around the vacuum, illustrate the behavior of the number of $e$-foldings during the reheating stage, $N_{reh}$, and of the final reheating temperature, $T_{reh}$, as functions of the scalar spectral index, $n_s$. We analyze our results with respect to the current bounds given by the PLANCK mission data and to upcoming cosmological experiments. We find that large values of the equation-of-state parameter ($w_{reh}>1/3$) are particularly favored as the scalar spectral index is of the order of $n_ssim 0.9680$, with a $sigma_{n_s}sim 0.002$ error. Moreover, we compare the behavior of the general reheating functions $N_{reh}$ and $T_{reh}$ in the Fibre Inflation scenario with that extracted by the class of the $alpha$-attractor models with $alpha=2$. We find that the corresponding reheating curves are very similar in the two cases.

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