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arXiv · 1902.02666

Radiative Axion Inflation

Abstract

Planck data robustly exclude the simple $\lambda\phi^4$ scenario for inflation. This is also the case for models of Axion Inflation in which the inflaton field is the radial part of the Peccei-Quinn complex scalar field. In this letter we show that for the KSVZ model it is possible to match the data taking into account radiative corrections to the tree level potential. After writing down the 1-loop Coleman-Weinberg potential, we show that a radiative plateau is easily generated thanks to the fact that the heavy quarks are charged under $SU(3)_c$ in order to solve the strong CP problem. We also give a numerical example for which the inflationary observables are computed and the heavy quarks are predicted to have a mass $m_Q \gtrsim 10^3TeV$.

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Andrea Caputo. 2019-02-07. Radiative Axion Inflation. https://doi.org/10.1016/j.physletb.2019.134824

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