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arXiv · hep-ph/0106320

Ultra High Energy Cosmic Ray, Superheavy Dark Matter and Extra Dimension

Kaoru Hagiwara·Yosuke Uehara
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Abstract

We propose a new mechanism for explaining the very long lifetime of superheavy dark matter X, which is proposed as a source of the ultra high-energy cosmic rays above the GZK cutoff (5 \times 10^{19} eV). The singlet X particle couples to the MSSM particles only through a bulk singlet field which develops the v.e.v. in the ``hidden'' brane. The distance between this hidden brane and the ``visible'' brane naturally leads to the exponential suppression of the coupling. The X particle decays predominantly into the higgsino and higgs boson of the MSSM, and its decay spectrum is completely determined once their properties are known.

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Kaoru Hagiwara, Yosuke Uehara. 2001-08-09. Ultra High Energy Cosmic Ray, Superheavy Dark Matter and Extra Dimension. https://doi.org/10.1016/s0370-2693(01)01021-8

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