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arXiv · 2106.02043

Ringing Non-Gaussianity from inflation with a step in the second derivative of the potential

Rakhi. R·Minu Joy
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Abstract

Inflationary model driven by a scalar field whose potential has a step in the second derivative with respect to the field is considered. For the best fit potential parameter values, the 3-point function and the non-Gaussianity associated with the featured model is calculated. We study the shape and scale dependence of the 3-point function. The distinctive feature of this model is its characteristic ringing behaviour of $f_{NL}$. We can see that the oscillations in $f_{NL}$ in this model last for a much longer range of k values, as compared to the previously studied models. In that sense, this model is potentially distinguishable from models with other features in the potential.

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Rakhi. R, Minu Joy. 2021-06-01. Ringing Non-Gaussianity from inflation with a step in the second derivative of the potential. https://doi.org/10.1007/s12043-022-02304-3

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