Power Spectrum Analysis of BNL Decay-Rate Data

TL;DR

This study investigates periodicities in nuclear decay data from BNL to identify potential solar influences, revealing a significant peak at 11.18 year^-1 linked to solar rotation, supported by rigorous statistical tests.

Contribution

It introduces new statistical tests, the shuffle and shake tests, to evaluate the significance of spectral peaks in decay data, strengthening evidence for solar influence.

Findings

Detected a significant peak at 11.18 year^-1 in decay data.

Found a major peak at 11.93 year^-1 with high statistical significance.

Provided evidence supporting solar rotation influence on nuclear decay rates.

Abstract

Evidence for an anomalous annual periodicity in certain nuclear decay data has led to speculation concerning a possible solar influence on nuclear processes. As a test of this hypothesis, we here search for evidence in decay data that might be indicative of a process involving solar rotation, focusing on data for 32Si and 36Cl decay rates acquired at the Brookhaven National Laboratory. Examination of the power spectrum over a range of frequencies (10 - 15 year^-1) appropriate for solar synodic rotation rates reveals several periodicities, the most prominent being one at 11.18 year^-1 with power 20.76. We evaluate the significance of this peak in terms of the false-alarm probability, by means of the shuffle test, and also by means of a new test (the "shake" test) that involves small random time displacements. The last two tests indicate that the peak at 11.18 year^-1 would arise by chance only once out of about 10^7 trials. Since there are several peaks in the search band, we also investigate the running mean of the power spectrum, and identify a major peak at 11.93 year^-1 with peak running-mean power 4.08. Application of the shuffle test and the shake test indicates that there is less than one chance in 10^11, and one chance in 10^15, respectively, finding by chance a value as large as 4.08.