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arXiv · 2310.11030

Primordial black holes and secondary gravitational waves from generalized power-law non-canonical inflation with quartic potential

Soma Heydari·Kayoomars Karami
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Abstract

Here, generation of PBHs and secondary GWs from non-canonical inflation with quartic potential have been probed. It is illustrated that, quartic potential in non-canonical setup with a generalized power-law Lagrangian density can source a consistent inflationary era with the latest observational data. Besides, we show that our model satisfies the swampland criteria. At the same time, defining a peaked function of inflaton field as non-canonical mass scale parameter $M(ϕ)$ of the Lagrangian, gives rise to slow down the inflaton in a while. In this span, namely Ultra-Slow-Roll (USR) stage, the amplitude of the curvature perturbations on small scales enlarges versus CMB scales. It has been illustrated that, further to the peaked aspect of the chosen non-canonical mass scale parameter, the amount of $α$ parameter of the Lagrangian has enlarging impact on the amplitude of the scalar perturbations. As a consequence of adjusting three parameter Cases of this model, three Cases of PBHs in proper mass scopes to explain LIGO-VIRGO events, microlensing events in OGLE data and DM content in its totality, could be produced. In the end, power-law behavior of the current density parameter of gravitational waves $Ω_{\rm GW_0}$ in terms of frequency has been examined. Also, the logarithmic power index as $n=3-2/\ln(f_c/f)$ in the infrared regime is obtained.

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Soma Heydari, Kayoomars Karami. 2024-02-07. Primordial black holes and secondary gravitational waves from generalized power-law non-canonical inflation with quartic potential. https://doi.org/10.1140/epjc%2Fs10052-024-12489-z

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