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A Lower Bound on Neutrino Mass and Its Implication on The Z-burst Scenario

Kwang-Chang Lai·Pisin Chen
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Abstract

We show that the cascade limit on ultra high energy cosmic neutrino (UHEC$ν$) flux imposes a lower bound on the neutrino mass provided that super-GZK events of ultra high energy cosmic rays (UHECRs) are produced from Z-bursts. Based on the data from HiRes and AGASA, the obtained neutrino mass lower bound violates its existing cosmological upper bound. We conclude that the Z-bursts cannot be the dominant source for the observed super-GZK UHECR events. This is consistent with the recent ANITA-lite data.

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Kwang-Chang Lai, Pisin Chen. 2005-11-22. A Lower Bound on Neutrino Mass and Its Implication on The Z-burst Scenario. https://arxiv.org/abs/astro-ph/0511340

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