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arXiv · hep-ph/9805397

Relic Abundance of Neutralinos in Heterotic String Theory: Weak Coupling vs. Strong Coupling

Y. Kawamura·H. P. Nilles·M. Olechowski·M. Yamaguchi
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Abstract

The relic abundance of stable neutralinos is investigated in $E_8 \times E_8'$ heterotic string theory when supersymmetry is spontaneously broken by hidden-sector gaugino condensates. In the weak coupling regime, very large scalar masses (compared to gaugino masses) are shown to lead to a too large relic abundance of the neutralinos, incompatible with cosmological observations in most of parameter space. The problem does not arise in the strong coupling regime (heterotic M-theory) because there scalar and gaugino masses are generically of the same order of magnitude.

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Y. Kawamura, H. P. Nilles, M. Olechowski, M. Yamaguchi. 1998-05-20. Relic Abundance of Neutralinos in Heterotic String Theory: Weak Coupling vs. Strong Coupling. https://doi.org/10.1088/1126-6708%2F1998%2F06%2F008

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