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Ultra High Energy Cosmic Rays: Strangelets? -- Extra dimensions, TeV-scale black holes and strange matter

R. X. Xu·F. Wu
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Abstract

The conjecture that ultra high energy cosmic rays (UHECRs) are actually strangelets is discussed. Besides the reason that strangelets can do as cosmic rays beyond the GZK-cutoff, another argument to support the conjecture is addressed in this letter via the study of formation of TeV-scale microscopic black holes when UHECRs bombarding bare strange stars. It is proposed that the exotic quark surface of a bare strange star could be an effective astro-laboratory in the investigations of the extra dimensions and of the detection of ultra-high energy neutrino fluxes. The flux of neutrinos (and other point-like particles) with energy >2.3 x 10^{20} eV could be expected to be smaller than 10^{-26} cm^{-2}$ s^{-1} if there are two extra spatial dimensions.

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R. X. Xu, F. Wu. 2003-03-15. Ultra High Energy Cosmic Rays: Strangelets? -- Extra dimensions, TeV-scale black holes and strange matter. https://doi.org/10.1088/0256-307x%2F20%2F6%2F308

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