Analysis of Beta-Decay Rates for Ag108, Ba133, Eu152, Eu154, Kr85, Ra226 And Sr90, Measured at the Physikalisch-Technische Bundesanstalt from 1990 to 1996

TL;DR

This study analyzes beta-decay rates of various isotopes measured over several years, revealing a consistent annual sinusoidal variation likely influenced by solar activity, with results obtained using a unique 4π detector setup.

Contribution

The paper provides the first detailed analysis of beta-decay rate variations over multiple isotopes using a 4π detector, suggesting a possible solar influence on decay rates.

Findings

Detected consistent annual sinusoidal variation in decay rates.

Amplitude of variation around 0.08%, statistically significant.

Results support a solar influence hypothesis, possibly excluding environmental factors.

Abstract

We present the results of an analysis of measurements of the beta-decay rates of Ag108, Ba133, Eu152, Eu154, Kr85, Ra226, and Sr90 acquired at the Physikalisch-Technische Bundesanstalt from 1990 through 1995. Although the decay rates vary over a range of 165 to 1 and the measured detector current varies over a range of 19 to 1, the detrended and normalized current measurements exhibit a sinusoidal annual variation with amplitude in the small range 0.068% to 0.088% (mean 0.081%, standard deviation 0.0072%, an 11{\sigma} rejection of the zero-amplitude hypothesis) and phase-of-maximum in the small range 0.062 to 0.083 (January 23 to January 30). In comparing these results with those of other related experiments that yield different results, it may be significant that this experiment, at a standards laboratory, seems to be unique in using a 4{\pi} detector. These results are compatible with a solar influence, and appear not to be compatible with an experimental or environmental influence. It is possible that Ba133 measurements are subject also to a non-solar (possibly cosmic) influence.