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arXiv · hep-ph/9805346

Superheavy Dark Matter with Discrete Gauge Symmetries

K. Hamaguchi·Yasunori Nomura·T. Yanagida
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Abstract

We show that there are discrete gauge symmetries protect naturally heavy X particles from decaying into the ordinary light particles in the supersymmetric standard model. This makes the proposal very attractive that the superheavy X particles constitute a part of the dark matter in the present universe. It is more interesting that there are a class of discrete gauge symmetries which naturally accommodate a long-lived unstable X particle. We find that in some discrete Z_{10} models, for example, a superheavy X particle has lifetime τ_X \simeq 10^{11}-10^{26} years for its mass M_X \simeq 10^{13}-10^{14} GeV. This long lifetime is guaranteed by the absence of lower dimensional operators (of light particles) couple to the X. We briefly discuss a possible explanation for the recently observed ultra-high-energy cosmic ray events by the decay of this unstable X particle.

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K. Hamaguchi, Yasunori Nomura, T. Yanagida. 1998-05-18. Superheavy Dark Matter with Discrete Gauge Symmetries. https://doi.org/10.1103/physrevd.58.103503

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