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arXiv · 1211.5662

Cosmological constraints on spontaneous R-symmetry breaking models

Yuta Hamada·Kohei Kamada·Tatsuo Kobayashi·Yutaka Ookouchi
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Abstract

We study general constraints on spontaneous R-symmetry breaking models coming from the cosmological effects of the pseudo Nambu-Goldstone bosons, R-axions. They are substantially produced in the early Universe and may cause several cosmological problems. We focus on relatively long-lived R-axions and find that in a wide range of parameter space, models are severely constrained. In particular, R-axions with mass less than 1 MeV are generally ruled out for relatively high reheating temperature, $T_R>10$ GeV.

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Yuta Hamada, Kohei Kamada, Tatsuo Kobayashi, Yutaka Ookouchi. 2013-04-30. Cosmological constraints on spontaneous R-symmetry breaking models. https://doi.org/10.1088/1475-7516%2F2013%2F04%2F043

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