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Do radioactive half-lives vary with the Earth-to-Sun distance?
J C Hardy1, J R Goodwin, V E Iacob
1Cyclotron Institute, Texas A&M University, College Station, TX 77843-3366, USA. hardy@comp.tamu.edu
Abstract:
Recently, Jenkins, Fischbach and collaborators have claimed evidence that radionuclide half-lives vary systematically over a ±0.1% range as a function of the oscillating distance between the Earth and the Sun, based on multi-year activity measurements. We have avoided the time-dependent instabilities to which such measurements are susceptible by directly measuring the half-life of (198)Au (t(1/2)=2.695 d) on seven occasions spread out in time to cover the complete range of Earth-Sun distances. We observe no systematic oscillations in half-life and can set an upper limit on their amplitude of ±0.02%.
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