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arXiv · hep-ph/9407322

Cosmological Constraints on the Scale of Supersymmetry Breaking

Raghavan Rangarajan
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Abstract

We consider the cosmological and astrophysical constraints on the decay of massive $E_8 \times E_8^\prime$ superstring axions associated with the hidden sector. We find that decay lifetimes greater than 1 s are ruled out by limits from nucleosynthesis, by limits on the distortion of the cosmic microwave and gamma ray backgrounds and by closure arguments. We conclude that $Λ>1.2\times10^{13}\gev$, where $Λ$ is the scale of gaugino condensation in the hidden sector. This implies that the scale of supersymmetry breaking is greater than $10^{10}\gev$. Significantly, our result agrees with the value of $5\times 10^{13}\gev$ for $Ł$ obtained independently by setting supersymmetric scalar masses equal to $m_W$.

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Raghavan Rangarajan. 1995-12-27. Cosmological Constraints on the Scale of Supersymmetry Breaking. https://doi.org/10.1016/0550-3213(95)00410-t

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