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F-term inflation in Superstring Theories

J. A. Casas·G. B. Gelmini·A. Riotto
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Abstract

A supersymmetric inflationary stage dominated by an $F$-term has the problem that the flatness of the potential is spoiled by supergravity corrections, that is the slow-roll parameter $η$ gets contributions of order unity. We show that in $F$-term inflationary models based on strings there is natural way of obtaining small values of $η$. This happens in models of hybrid inflation based on orbifold constructions, in which a modulus $T$ field is responsible for the large value of the potential during inflation, and a second field $ϕ$ with appropriate modular weight is responsible for the roll-over. We illustrate the mechanism with a model in which the inflaton potential is provided by gaugino condensation, leading to succesful inflation.

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J. A. Casas, G. B. Gelmini, A. Riotto. 1999-03-25. F-term inflation in Superstring Theories. https://doi.org/10.1016/s0370-2693(99)00683-8

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