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arXiv · 1007.5152

Constraint on the gravitino mass in hybrid inflation

Kazunori Nakayama·Fuminobu Takahashi·Tsutomu T. Yanagida
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Abstract

We revisit the F-term hybrid inflation model in supergravity. In particular, we point out that a constant term in the superpotential has significant effects on the inflaton dynamics. It is shown that the hybrid inflation model suffers from several potential problems: tuning of the initial condition, gravitino overproduction and formation of cosmic strings, for both minimal and non-minimal Kahler potentials. These problems can only be avoided in gauge-mediated SUSY breaking models where the gravitino is relatively light and the constant term in the superpotential is not important. Implications on the non-thermal leptogenesis scenario are also described.

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Kazunori Nakayama, Fuminobu Takahashi, Tsutomu T. Yanagida. 2010-07-29. Constraint on the gravitino mass in hybrid inflation. https://doi.org/10.1088/1475-7516/2010/12/010

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