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arXiv · 2301.07920

Continuous Spectrum on Cosmological Collider

Shuntaro Aoki
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Abstract

We study the effects of a massive field with a continuous spectrum (continuum isocurvaton) on the inflationary bispectrum in the squeezed limit. As a concrete example, we extend the quasi-single field inflation model to include a continuum isocurvaton with a well-motivated spectral density from extra dimensions and focus on a contribution to the bispectrum with a single continuum isocurvaton exchange. In contrast to the usual case without the continuous spectrum, the amplitude of the bispectrum has a damping feature in the deep squeezed limit, which can be strong evidence for the continuous spectrum.

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Shuntaro Aoki. 2023-01-19. Continuous Spectrum on Cosmological Collider. https://doi.org/10.1088/1475-7516%2F2023%2F04%2F002

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