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arXiv · 1709.04610

Gravity Waves and Gravitino Dark Matter in $μ$-Hybrid Inflation

Nobuchika Okada·Qaisar Shafi
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Abstract

We propose a novel reformulation of supersymmetric (more precisely $μ$-) hybrid inflation based on a local U(1) or any suitable extension of the minimal supersymmetric standard model (MSSM) which also resolves the $μ$ problem. We employ a suitable Kahler potential which effectively yields quartic inflation with non-minimal coupling to gravity. Imposing the gravitino Big Bang Nucleosynthesis (BBN) constraint on the reheat temperature ($T_r \lesssim 10^6$ GeV) and requiring a neutralino LSP, the tensor to scalar ratio ($r$) has a lower bound $r \gtrsim 0.004$. The U(1) symmetry breaking scale lies between $10^8$ and $10^{12}$ GeV. We also discuss a scenario with gravitino dark matter whose mass is a few GeV.

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Nobuchika Okada, Qaisar Shafi. 2018-10-30. Gravity Waves and Gravitino Dark Matter in $μ$-Hybrid Inflation. https://doi.org/10.1016/j.physletb.2018.10.057

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