Power Spectrum Analysis of Physikalisch-Technische Bundesanstalt Decay-Rate Data: Evidence for Solar Rotational Modulation

TL;DR

This study finds evidence of solar rotational modulation in nuclear decay rates by analyzing data from PTB and BNL, revealing consistent periodicities around 11.2/yr, suggesting a possible solar influence on nuclear processes.

Contribution

It provides the first combined analysis of PTB and BNL decay data showing a significant peak at ~11.2/yr, indicating solar rotation effects on decay rates.

Findings

Significant peaks at ~11.2/yr in decay data from PTB and BNL.

Combined analysis yields a highly significant peak at 11.23/yr.

Results suggest a possible solar influence on nuclear decay processes.

Abstract

Evidence for an anomalous annual periodicity in certain nuclear decay data has led to speculation concerning a possible solar influence on nuclear processes. We have recently analyzed data concerning the decay rates of Cl-36 and Si-32, acquired at the Brookhaven National Laboratory (BNL), to search for evidence that might be indicative of a process involving solar rotation. Smoothing of the power spectrum by weighted-running-mean analysis leads to a significant peak at frequency 11.18/yr, which is lower than the equatorial synodic rotation rates of the convection and radiative zones. This article concerns measurements of the decay rates of Ra-226 acquired at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. We find that a similar (but not identical) analysis yields a significant peak in the PTB dataset at frequency 11.21/yr, and a peak in the BNL dataset at 11.25/yr. The change in the BNL result is not significant since the uncertainties in the BNL and PTB analyses are estimated to be 0.13/yr and 0.07/yr, respectively. Combining the two running means by forming the joint power statistic leads to a highly significant peak at frequency 11.23/yr. We comment briefly on the possible implications of these results for solar physics and for particle physics.