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Neutron Moderation in the Oklo Natural Reactor and the Time Variation of alpha

S. K. Lamoreaux
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Abstract

In the analysis of the Oklo (gabon) natural reactor to test for a possible time variation of the fine structure constant alpha, a Maxwell-Boltzmann low energy neutron spectrum was assumed. We present here an analysis where a more realistic spectrum is employed and show that the most recent isotopic analysis of samples implies a non-zero change in alpha, over the last two billion years since the reactor was operating, of Δα/α\geq 4.5\times 10^{-8} (6σconfidence). Issues regarding the interpretation of the shifts of the low energy neutron resonances are discussed.

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S. K. Lamoreaux. 2004-03-24. Neutron Moderation in the Oklo Natural Reactor and the Time Variation of alpha. https://doi.org/10.1103/physrevd.69.121701

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