Evidence of correlations between nuclear decay rates and Earth–Sun distance

Unexplained periodic fluctuations in the decay rates of 32Si and 226Ra have been reported by groups at Brookhaven National Laboratory ( 32Si), and at the Physikalisch–Technische–Bundesanstalt in Germany ( 226Ra). We show from an analysis of the raw data in these experiments that the observed fluctuations are strongly correlated in time, not only with each other, but also with the time of year. We discuss both the possibility that these correlations arise from seasonal influences on the detection system, as well as the suggestion of an annual modulation of the decay rates themselves which vary with Earth–Sun distance.