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High-frequency Graviton from Inflaton Oscillation

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 نشر من قبل Kazunori Nakayama
 تاريخ النشر 2020
  مجال البحث فيزياء
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We point out that there is a high-frequency tail of the stochastic inflationary gravitational wave background that scales as $f^{-1/2}$ with frequency $f$. This contribution comes from the graviton vacuum fluctuation amplified by the inflaton coherent oscillation during the reheating stage. It contains information on inflaton properties such as the inflaton mass as well as the thermal history of the early Universe.



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