We obtain new, more accurate limits of − 4 × 10 − 17 ⩽ α Following tradition, we have used formulas of Damour and Dyson to estimate the rate of change of the fine structure constant α. Contrary to the results of previous papers, we found no evidence of a change of the samarium cross section: a possible shift of the resonance energy is given by the limits − 73 ⩽ Δ E r ⩽ 62 meV.
The averaged cross section of 62 149 Sm and its dependence on the shift of a resonance position E r (due to variation of fundamental constants) are significantly different from previous results. The Oklo natural fossil fission reactors in Gabon, Equatorial Africa, have been studied as a natural analogue for spent nuclear fuel in a geological. The conditions under which a natural nuclear. As would be expected, we found for the fresh core a significant difference between reactor and Maxwell spectra, which had been used before for averaging cross sections in the Oklo reactor. Organic matter in the Oklo natural reactors 7-9 could have important effects on radionuclide containment. A natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions occur. These fission reactions were sustained for hundreds of thousands of years until a chain reaction could no longer be supported. We also estimated the temperature and void effects for the fresh core. Oklos Natural Fission Reactors More than 1. The natural nuclear reactor formed at Oklo in Gabon, Africa, when a uranium-rich mineral deposit became flooded with groundwater that acted as a neutron moderator, and a nuclear chain reaction started. That is because influences the rate of various nuclear reactions. Multiplication factors, reactivities, and neutron fluxes were calculated. The natural reactor of Oklo has been used to check if the atomic fine-structure constant might have changed over the past 2 billion years. The calculations were performed for three fresh cores with different uranium contents. We constructed a computer model of the Oklo reactor zone RZ 2 which takes into account all details of design and composition.
#Oklo natural reactor code
For reliability, we used recent versions of two Monte Carlo codes: the Russian code MCU-REA and the well-known international code MCNP. These calculations are in progress.Using modern methods of reactor physics, we performed full-scale calculations of the Oklo natural reactor.
The reactors occur as small lenticular bodies of high-grade uranium ore (2060 by weight) in the uranium ore deposits. 4 10^Ī further improvement in the accuracy of the limits can be achieved by takingĪccount of the core burnup. Natural nuclear reactors have been discovered in the Oklo and the associated Okelobondo and Bangombe uranium ore deposits in the Republic of Gabon on the coast of Equatorial West Africa. Significantly different from previous results.Ĭontrary to results of some previous papers we find no evidence for theĬhange of the fine structure constant in the past and obtain new, most accurate Of resonance position (due to variation of fundamental constants) are The averaged cross section of Sm-149 and its dependence on the shift A bizarre consequence of the appearance of oxygen was the advent the worlds. Spectra, which was used before for averaging cross sections in the Oklo From James Lovelock, The Ages of Gaia (1988). Oklo Mine, located in Oklo, Gabon on the west coast of Central Africa, is believed to be the only natural nuclear fission reactor. As would be expected, we haveįound for the fresh core a significant difference between reactor and Maxwell Temperature and void effects for the fresh core. Reactivities and neutron fluxes were calculated. The calculations were performed for threeįresh cores with different uranium contents.
We have constructed aĬomputer model of the reactor Oklo zone RZ2 which takes into account allĭetails of design and composition. Version of two Monte Carlo codes: Russian code MCU REA and world wide knownĬode MCNP (USA).
#Oklo natural reactor pdf
Download a PDF of the paper titled Natural Nuclear Reactor Oklo and Variation of Fundamental Constants Part 1: Computation of Neutronics of Fresh Core, by Yu.V.Petrov and 4 other authors Download PDF Abstract: Using modern methods of reactor physics we have performed full-scaleĬalculations of the natural reactor Oklo.
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