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arXiv · hep-ph/9904438

Superheavy Dark Matter and Thermal Inflation

T. Asaka·M. Kawasaki·T. Yanagida
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Abstract

The thermal inflation is the most plausible mechanism that solves the cosmological moduli problem naturally. We discuss relic abundance of superheavy particle $X$ in the presence of the thermal inflation assuming that its lifetime is longer than the age of the universe, and show that the long-lived particle $X$ of mass $10^{12}$--$10^{14}$ GeV may form a part of the dark matter in the present universe in a wide region of parameter space of the thermal inflation model. The superheavy dark matter of mass $\sim 10^{13}$ GeV may be interesting in particular, since its decay may account for the observed ultra high-energy cosmic rays if the lifetime of the $X$ particle is sufficiently long.

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T. Asaka, M. Kawasaki, T. Yanagida. 1999-09-13. Superheavy Dark Matter and Thermal Inflation. https://doi.org/10.1103/physrevd.60.103518

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