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Production and dilution of gravitinos by modulus decay

Kazunori Kohri·Masahiro Yamaguchi·Jun'ichi Yokoyama
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Abstract

We study the cosmological consequences of generic scalar fields like moduli which decay only through gravitationally suppressed interactions. We consider a new production mechanism of gravitinos from moduli decay, which might be more effective than previously known mechanisms, and calculate the final gravitino-to-entropy ratio to compare with the constraints imposed by successful big bang nucleosynthesis (BBN) etc., taking possible hadronic decays of gravitinos into account. We find the modulus mass smaller than $\sim 10^4$ TeV is excluded. On the other hand, inflation models with high reheating temperatures $T_{R,\rm inf} \sim 10^{16}$ GeV can be compatible with BBN thanks to the late-time entropy production from the moduli decay if model parameters are appropriately chosen.

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Kazunori Kohri, Masahiro Yamaguchi, Jun'ichi Yokoyama. 2004-04-22. Production and dilution of gravitinos by modulus decay. https://doi.org/10.1103/physrevd.70.043522

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