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arXiv · 1110.2072

R-Symmetry and Gravitino Abundance

Ioannis Dalianis
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Abstract

Supersymmetry breaking sectors generically have an approximate global U(1) $R$-symmetry. Thermal effects tend to restore the $R$-symmetry in the reheated early universe. We revisit the gravitino generation from the thermal plasma and we argue that an $R$-symmetric phase suppresses the gaugino masses and thereby the production of the helicity $\pm 1/2$ gravitino component. For reasonable values of the hidden sector parameters the gravitino can account for the dark matter of the universe with a relic abundance characterized by a remarkable insensitivity to the reheating temperature.

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Ioannis Dalianis. 2011-10-18. R-Symmetry and Gravitino Abundance. https://doi.org/10.1103/physrevd.85.061301

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